PHYSICS TEST-18 VIDEO SOLUTION FOR RE NEET-2026

[00:00:00]Goal Nations [Music] Leading Institute Hello students welcome to all in the session of Rennet Test Test No. 18 Held on 14th of June 2026 Late Start Hour Discussion. Now the first question is a Particle is executing simple Harmonic motion with time period 2t period with which its kinetic energy Oscillates. Look, we know here If we consider the SHM of the particle x = a sinomegat + Let's take the initial fuzz to be zero here.

[00:00:35]The value of x is given and you have a sinomegat This is the displacement equation of SHM If we delimit it for time You will get velocity in respect whose value is a omegomegat Instead of writing these steps, if you directly If you had remembered the formula, you could have directly could write the formula that is 1/2 mv² will b = 1/2 m omega² a² * cos² omegat what Are we writing? Instantaneous here I'm writing kinetic energy because Here pay is in terms of time. But one This kinetic energy can be calculated using the formula can be rearranged. That is 1/2 mom² a² and we know that formula. 1 + cos 2omegat / is equal to 2 because I know a formula cos 2 theta cos 2 theta is 2 cos² theta - 1 and from here if cos² of theta If we write the value then 1 + cos 2 theta / 2 Here, instead of theta, we write omegat like this Then if we rearrange it further then it becomes kinetic Energy has come to you, it has been multiplied So 1/4m² Multiplied by a² + 1/4 becomes 2 * 2 There are 4 momg² a² and this is cos 2omegat this is Kinetic energy is a constant term but This one is showing the oscillating term.

[00:01:55]in which now if the angular frequency In the initials here it was omeg, so now it has changed to got 2 omega so let's see here that omeg' has an initial value of 2 Times so [sound of clearing throat] We can write 2π / t' = 2 times 2π / equal to t so from here to And look at the time period given here.

[00:02:16]Is. Sorry time period here in initials Given 2t, so put here in place of t We will 2t all the values ​​here After the pay cut, the time period came new i.e. kinetic energy equal to t So the option will show you here in second Next Question number second Edge telescope in an observatory has an Objective of focal length 32 meters and end And an eye piece of focal length 2 cm. If If you look carefully, the focal length of the eye piece is 2 cm Is. The value of FO is given as 32 meters Is. So it means here is the position of U That's too much for long distances He is talking. Very fine means It is at an infinite distance. of the telescope Using in normal adjustment mode.

[00:03:07]So here we know that the value which will be V The final image will be its value.

[00:03:12]That will be equal to FO.

[00:03:15]In normal adjustment the telescope is used to see the moon what is the diameter Of the image of the moon formed by the Objective Given That the Diameter of the Moon This is the radius of the lunar orbit Round the Earth is given, that is, for For example, let's assume something like this: You have this moon, so this moon is here.

[00:03:32]You are creating the image, see how here.

[00:03:34]You did the image form here According to the question, this is the image The form is asking what its diameter is.

[00:03:42]It will be if its diameter is given here.

[00:03:45]So let's write down its diameter as d From. Its diameter is written as d'.

[00:03:51]I came to know that the distance it is from here The image formed is equal to v = fo. These Learn from the concept. This one by Joe Lunor We have given him orbit from here.

[00:04:01]You can write O. Angular is going to be built here.

[00:04:03]Angle saw here alpha. what here Did you see it here? Beta. Know here We can write tan alpha = tan beta. because Here alpha = beta. If here If alpha = beta then tan alpha = tan beta and tan alpha can be written as perpendicular Divided by base = Perpendicular divided The value of the base value here is fd0 equals d' you will get that is d * fo / ro equals Diameter of the Moon Mansion done 3 * 10 to the power 6 so 3 * 10 to the power 6 Write the lunar orbit here The distance is given as 4 * 10 ^ 8 I wrote it down. The value of FO is 32.

[00:04:46]Equal to the meter. Look at this it went up Here. If this is cut then it becomes eight. These 24 was found * 10 to the power -2 was shown to We could have written 24 cm here. So You will see the option here first.

[00:05:04]Next Question number three.

[00:05:13][sound of throat clearing] A body covers a Distance of 8 meters in fourth second and 24 Meter in sixth second. See what all Was it said here? Fourth in the first case The distance traveled in seconds Its value has been given to you question 8 meters in. But when? In the fourth second.

[00:05:30]Then next it was said here this The value of distance is s2 = 24 m.

[00:05:36]In the sixth second. As such. is speaking again If the motion is uniformly accelerated. Correct Is? How Far Will You Travel in the Next Four Seconds? So how much will this happen in the next four seconds?

[00:05:48]Will the distance work? This was asked of you. So This distance of the next four seconds Question mark. First here, first Find out according to these two conditions Let us find out the values ​​of u and a.

[00:05:59]that it will have initial speed u and Constant acceleration means uniformly If there is accelerated motion then there will be a. first his Let's find out the values. So you know s = u + 2n - 1 * a / 2 such a formula You know, we write the formula.

[00:06:15]Distance traveled in n time. So here got 8 = u + 2 here the value of n is four Is. So you get 4 * 2, if you do 8 - 1 Here we go, 7a / 2 equation number one.

[00:06:27]Similarly, you wrote 24 = u + now this 2n - 1 will become 12 - 1 i.e. 11 will become 11a / 2 equation number two minus both Given 2 - 1, write it down. If 2 - 1 is done then 24 - 8 done 16 came. u to u got cut.

[00:06:46]11a and 7a so you are left with 5a / 2 equals 5 sorry 11 and this 4a / 2 aa Will go. Sorry, let's fix it. No 5 4a/2 will come. This is the 4a/2 so it's done You have 2a, so the value of a is 8 meters.

[00:07:05]But Second Square. put it in a They give it in the forest. Like if put in the forest 8 = u + 7 * a has the value 8 / 2 so this 4 is cut, this becomes 28. So the value of u is It came to -20 meters per second. Now it is asked that How much distance in the next 4 seconds Will you travel? So actually from here If it has six seconds while moving So in the next 4 seconds, four out of six What did you get when you added it? 10 means that 10 Cover here in seconds and before that If the distance between them is 6 seconds If you find out the difference then you can tell from here You can guess what will happen in the next 4 seconds.

[00:07:44]Will go the distance. So in the next 4 seconds See how I am writing it. So Distance S will be equal to distance Traveled in 10 seconds. make it minus Distance travelled in 6 seconds. 6 seconds If I subtract the distance I walked Here we will add fourth and That means in 10th you will get the next 4 Distance of seconds. So, talking about the S10.

[00:08:07]Now here's why it is not a nth and nth of Know the formula Sn = Sn - Sn - 1 The same concept is being used here. So You got to see this result. But here There was a difference, 10 more on saying next four.

[00:08:20]That's why six is ​​written like this. So this happened Value ut + 1/2 at² in time 10 seconds rewrite the minus you put here + 1/2 at² but at time t = 6 seconds then s = Put the value here -20, the value of t is If a is 10 then the value of 200 + 1/2 a is 8 * this 100 is written as its value in minus multiply this by 20 and here But you have this six so 120 20 minus I plus half half this becomes 8 and this becomes There you have it, all 36 values ​​here.

[00:08:57]We will solve it by putting it on pay. It cuts through this If it is done then it becomes four then the value of s is yours It's close - 200 + 400 minus minus this Plus it is, that is 120, then this minus here.

[00:09:09]This will be deducted from this, if it becomes four then minus Solving this 144 gives the value of s You have 176 meters, so you see the option Four here Next Question number three which of the following The circuit provides full wave rectification off n input? Look here at the four diodes.

[00:09:37]was used. So this bridge rectifier Done. Operation of a bridge rectifier If you want to talk about it here, then directly here Let's say if the AC input is AC input If this is the positive terminal then Correspondingly this negative terminal here You can write this on this positive terminal This is the negative terminal, if this is the positive terminal They know this is the P side, this is the N side.

[00:09:56]And this would have been the N side here, this would have been the P side So there you have it, forward bias, whereas There you have it, reverse bias in this case.

[00:10:04]I have this you have N this P so this become There will be forward bias and this will happen.

[00:10:10]You have this reverse bias here if this There is forward bias in the first case and in the second case If I talk about it then during positive now this Let's give it a name, shall we?

[00:10:19]Let's call it d1 here, let's call it d2 I am saying this, I have called it d3 and this If you say d4 then during the positive half Look at the cycle of the input signal.

[00:10:29]Let's talk about the positive here first.

[00:10:31]Half of this is about input and output.

[00:10:33]If you do this, you will get the output here.

[00:10:35]Rectified Output This is the output with Respect to time t with respect to Looking at the above here. So here what You get the output in the positive half cycle Conducted you have D1 and then Conducted Who did it here D4 so which is diagonally Opposite you had Dupole, both of them were conductors By doing this I got the output here, the other two If reverse bias is open then the output You got the accordion of these two here.

[00:10:59]Named similarly to D1 and D4 when negative Half cycle came here, so this terminal Negative Corresponding This Positive So Here You can also write this terminal negative on Correspondingly this positive now just reverse Will be done If it is positive then it is reverse bias. it There will be forward bias. If it is negative then it There will be forward bias. This will be reverse bias.

[00:11:18]This time diagonally you have from D2 and D3 You will get the output. That means you will get D2 here.

[00:11:23]and D3 from And So On. Is such a process Are you seeing it in anyone else? check it Let's take it. See the first one here If this is positive, this is negative, then this forward bias, this forward bias, so the current It came like this. Both of these are reverse bias, so this I did not find the combination. because here As soon as it comes near it, it opens.

[00:11:40]If he comes here, it will open. So here The output will be zero. So you are not first Can. Similarly, here if you have seconds Let's go here in seconds, positive this Came negative. So here these two reverse Both the biases here are forward bias. So He will not conduct it. So this is also zero.

[00:11:53]So you see option three here. This way You can also check out Four. If here See, this has become a plus. This became a minus.

[00:12:00]So this reverse bias. This forward bias. open The circuit will not pass any current. So this That also went wrong. I'll show you the option here Three. Next.

[00:12:14]Question number five A block of mass 3 kg dropped from a height of 75 cm on a spring whose force The constant is 2400 newtons per meter.

[00:12:25]Maximum distance through which the spring Is compressed by asked what will happen?

[00:12:30]That is, look here, let's assume this is a It is spring. Something like this was placed here Is. There is a ball here that is from a height h Dropping from here. So u0 whose mass m on maximum compression Let's say when this ball comes here Will stop. Watch this, this is the maximum.

[00:12:49]Compression. Come here to the momentary ball Have to stop. will be. Otherwise it always I would start compressing. So this is its This is the initial position. So let's assume compress If it is done here then let us write d. Whereas What is this value here? equal to h.

[00:13:03]So this is the initial and this is the final position. then that The compression that came in the case is what we We will write the maximum compression here. So Let's assume d here. That's what I have to find out.

[00:13:12]so from kw If we talk about kinetic theory here then Work Done by All Is Equal to Change in Kinetic energy can be written like this. Here Pay Work Done by Gravity and another Work Done Bye Spring. The remaining third is no other F = k final - k initials dropped u0 then k Zero initial came and stopped maximum In compression, the final energy is also zero.

[00:13:37]This is also zero. So Work Done By Gravity gives you found. Plus work done by spring force The sum that comes out is equal to zero. Work Done By Speaking of gravity, mg is on the bottom.

[00:13:47]It seems. The motion is also downward.

[00:13:49]So you have mg times but h + d because it's between here and here Has been. And that's where we know the spring force.

[00:13:56]Are. What is this? - 1/2 k * d² = 0 So you wrote here mg + d = 1/2 k * d² All the values ​​are given to you here.

[00:14:09]We will solve it by putting the values. give mass I have kept you three. So write three here.

[00:14:13]Take the value of g as 10. The value of h is your Pass 75 cm so 10 to the power -2 Write down plus d = 1/2. This gives you 2400 2400.

[00:14:26]into here write d² this is cut from this So here it is, this 10 is cut from 10.

[00:14:33]If this is deducted from three then we get 40.

[00:14:36]The value you got is d + 0.75 = 40d² So look here, make one.

[00:14:45]The quadratic equation you now need to solve If we write equation 0 then the formula for Shadhachar is If we use d = -b, then minus b here.

[00:14:54]Knowing the value here is equal to one.

[00:14:56]If it is -b then it becomes one plus minus under root b squared i.e. 1 square minus of minus 4ac because c Negative, so plus the value of a You have 40 divided into 75.

[00:15:11]The value of buy 2 * a is given to you Equal to 40 here. such as its values When solved, the value of d came out You have 15 cm. Then I showed you the option Four here.

[00:15:26]Next Question number six. Assertion and Reason Based Nuclear Force Between Neutrons neutron proton and neutron and Proton. Proton is approximately the same.

[00:15:44]This is correct. Because you know because The nuclear charge is based on the charge It doesn't depend. The charge was independent Is. So, this Reese is also correct. So, both Assertion and Reason are correct and Reason is the Correct explanation of assertion. So, the option Show seconds. Next.

[00:16:04]Question number seven. If 10 to the power 27 gas Molecules Etch Mass of 10 to the Power -26 kg Colloid with a surface perpendicular to it Elastically per second. See Elastically What does it mean to come? Perpendicular if If it collided, then after colliding perpendicularly I just rebounded and went back.

[00:16:23]Will go. At the same speed at which you come Hit back with the same speed.

[00:16:29]over an area of ​​5 meter square with the Speed ​​of 10 to the power 5 meters per second. The Pressure exerted by the gas molecules.

[00:16:35]So we know the pressure. What happens?

[00:16:37]Force/Area. If the force is detected here If you do it, will you write it before that? change in Momentum during collision. Change in Momentum Speaking of P final - P initial. Any If one direction is considered positive then this The direction will become negative. So here The value you will get is equal to 2mv.

[00:16:54]But, here as soon as the pressure If I get it, can I write Force? Force How much will it be exerted? So you know n Times of dp / dt or delta p / delta t So you have got these values ​​2nmv But if second is called then the value of t is one Went here and as soon as I got the force, I picked it up.

[00:17:11]If I put it here, the pressure came.

[00:17:13]The value of that is 2n mass * velocity Divided by area, the pressure is given by p = 2n You have 10 to the power 27, so 27 is written Mass is 10 to the power -26, speed is 10 to The Power 5 Meter Per Second Area Question I have given five here, so look at it.

[00:17:34]Values ​​this is cut from here so 10 The remaining 10 to the power six is ​​here.

[00:17:38]The pressure reached 0.4 * 10 to the power here is six which is written We could have 4 * 10 to the power 5 Newton per meter square is the pressure The value you get is 4 * 10 to the power 5 Newton per meter square option is shown.

[00:17:54]First Next Question number at in the given circuit the The potential at point B is zero. The What will the potential at points A and D be?

[00:18:10]will be? The potential of A and D has to be told. If Here B is zero, so we know from KVL Kirchhoff's Voltage Law Between We are looking at points A to B. only Started walking from A and moved ahead to VA. That There is resistance in the direction in which there is current.

[00:18:24]So -i * R equals B. So From here VA equals to IR because B The potential of is said to be zero. of current The value given here is three.

[00:18:36]Resistance is fourth. So here it comes to 12 equal to volts. So option first or second Or third cannot be fourth. This is wrong Went. Move ahead. This is how we use KVL.

[00:18:45]do. From kval between points this time Taking a walk between A and D If you start with VA -i * R then now you understand 4 * 3 -i * R so 3 * 2 written minus and here Pay plus polarity which will get last here We will write the path because this is ours.

[00:19:06]Following through this path. So Last here the polarity reached +4 d Near. The value of A you just mentioned is 12.

[00:19:14]This also becomes -12, this becomes 6 + 4 = this comes If VD is cut from 12 to 12 then VD Showing you the value from here minus 2 2 volts of volt minus and this 12 so option I show you three here Question number nine the ratio of radii of Earth to another The ratio of the planet is 4/3 Radii of Earth to the planet is given.

[00:19:44]That is, the radius of the planet to the red star Radius of Earth to another planet. write upside down Are taking. See the radius of the Earth here To the planet. This is the first information given In the question. Wrote 4/3 4/3. and there Ratio of mean density. so the density of Earth divided by density of planet. it Also given equal to 7/5. If an Astronauts can jump to a maximum height of 1.8 meters on the Earth with the same effort Maximum Height He Can Jump on the Planet What will happen? I have to tell you this. So Look, we know here that first of all we have to do with g.

[00:20:22]If we talk, we can write it in terms of density is 4/3π rg * r so d here g of Earthe/g of Planet. So the density of Earthed by Planet and Radius of Earthed By radius of planet. So this is the result You have it 7/5 and it's given to you 4 / 3 So here it is 28 / 15 As soon as this If you get it, you know that the maximum height The formula h max = u² / 2g so here We have to write h Max which is becomes inversely proportional to 1 / g, so writing here h of planet by h of Earth will be equal to ho jayega g of Earth Divided by g of planet inverse inversely proportional whose value is your Pass Aaya 28 / 15 So Height in a Planet How much will it jump when it reaches the planet?

[00:21:19]For main, we will write 28/15 here.

[00:21:23]Height of a man which covers maximum height If it is on Earth then it is equal to 1.8 If we solve it from here then the height of man in A Planet Has Arrived 3.36 You can see the option equal to the meter here.

[00:21:37]Four Next Question number 10 Statement Base Initially There Is No Current In the circuit, the key is closed at time T = 0 Bulb B1 glows gradually while bulb B2 Glows Instantly at Time T the Key Is Switched off bulb B1 dies gradually while Bulb B2 dies instantly. Look, we are Let us know here what this LR actually is.

[00:22:10]There is a circuit. Bulbs are connected in series.

[00:22:13]So there will be some resistance to this. So This combination gives you an LR circuit.

[00:22:18]is the LR circuit of. So what will you do here?

[00:22:20]Pay? As soon as you close the key, plus The minus current will be stable here. But The value of the current is here It will start increasing gradually. to whom We write I = I not 1 - e of ^ -t / Tau. For which the current growth is Current is seen in respect of t I mean, it's called something like this here.

[00:22:42]Growth half current is called tau here.

[00:22:45]Here this time constant which is l / r so here the value of current is immediate Here it will not glow slowly As the current starts growing here So this bulb will start glowing here.

[00:22:57]So here statement one is looking current.

[00:22:58]And as you establish this connection If you do this, then immediately switch it off here.

[00:23:03]Doing it gradually does not mean taking dice Immediate dice will not do. Dice gradually Will do. While there is resistance here, Energy storage of any energy here Devices not connected. Neither is an inductor And neither is the capacitor. So the current here The immediate value will change. While the inductor And this value in respect of resistance Gradual increase or gradual decrease Will do. So the first statement is correct.

[00:23:26]Second bola hai inductor apos any change in Magnetic Flux and Its Change in Current Through it. By discussing this property If you are speaking here then statement too is correct Is. So both statement one and statement two R Correct. So I showed you the option here.

[00:23:39]Seconds.

[00:23:41]Next Question number 11. A wire of length 12 inches A linear mass density mu area of ​​cross Section A and Young's modulus Y. it is suspended vertically from a rigid support The Extension Produced by The Wire Due To It's own weight. When it comes to own weight First, let's talk about extensions here.

[00:24:07]So we can write f * l / y * a Equal and it came on its own weight weight. So Here mg and this is the distance we take.

[00:24:17]Now we will take this from the center of mass. When these are their Extension in this due to own weight will produce divided by y * a now Look here in your given question.

[00:24:28]Mass per unit length is linear Mass density, whose value here is μ, This gives us a value equal to m/2l, which we can call People are writing m/2l here so what Instead of capital m, we will write μ * 2l like this And here you have the question of I If you have given 12 instead, then we will write that.

[00:24:49]Look, now according to the question Let's write extensions, replace capital m with aa gone μ * 2L like this write * g write into If the length you have in the question is 2L then 2L Put divided by here y * a area And here the value of Young's modulus Mentioned two to two cut result This came to you 2 mU 2 mgµg² / y * a then 2 mu u l² /y * a option is shown to you here first next question Question number 12 The relation between an AC voltage source and Time in SI units is v = 220 sin 200 * cos 200 volts the value of peak voltage And frequency will be respectfully.

[00:25:44]First convert it into that format.

[00:25:46]Those who have standard format It happens. So what did you do here? 220 / 2 * multiplying 2 to above and below Are. That is sin 200πt * cos 200πt What did you do here? Two to top down Multiplied because you have it here Both sin and cos came. This is standard in the format v = v not in sinomegat are converting. Then see the result So you have this 110 of 2sinθ * cos theta The result is sin 2 times theta, that is equal to 200π * t compared from here So v = to, this result came to you v not sin omegat and omeg are written as 2πf. ask I am telling you that the peak voltage here, so The peak voltage value you have is 110 That is equal to 110 volts. So, 110 volts If yes, there is an option, then it will be second, then it will be third Went. Secondly, frequency was asked. So, The value of omega here is omega.

[00:26:44]The value of is equal to 2 * 200π. and Omega This is equal to 2πf = 200 pi. So, here to 2π 2π cut off. So, the frequency of The value that has come is 200 Hz. 200 Hertz 110 volts. Then I showed you the option Equal to three here. Next Next Question. Question number is 13. A Fighter Plane flying horizontally at the attitude of 18 km With speed 900 km. per hour Passes directly overhead and anti-crop gun at what angle from the vertical should the Gun be fired for the shell with muzzle speed 800 Meter Per Second To Hit The Plane G Take Tech Have to do it. The value of g is equal to 10. See Let's say there's a fighter plane here.

[00:27:24]Which is 4900 km. at the speed of per hour Which has 5/18 meter per second, then this value will come You have 250 meters per second.

[00:27:33]It is on some attitude. one here one here You have an anti-aircraft gun.

[00:27:38]Which is giving muzzle speed here is 800 meters per second. 800 meters per second Fired at a speed of. angle from vertical This was said on Theta. Look at this then will be able to hit here when horizontal velocity of this and this projectile motion The horizontal velocity should be the same. If its If we consider speed as v here, then this You'll see v sin theta. So here pay to Horizontal of both to be hit The speed should be the same. That is 250 will be Equal to 800 * sin theta. As such Write. So this is cut off from this. So sin theta The value that came out was 25 / 80 25 / 80 So if we divide it by 5 then it becomes 5/16.

[00:28:27]The value of theta becomes sin inverse 5/16 so You will see the option here Pay Four Next Question No. 14 The Resistance of a Germanium Junction Diode Hus Vi Meaning Characteristics as shown in the figure where Pay its low voltage i.e. cut voltage The current asked for is kept equal to 0.3 volts What should be the value of resistance here?

[00:28:57]So we know R = deltaV / deltaWrite You can have the value of deltaV 2.7 - The value of VK is equal to 0.3, so that Portion will be this show will do DeltaV and right here The value of pay current given is 12 mill If we got amperes then write 10 to the power -3.

[00:29:18]Its value has come to you minus here Upon happening. That is 2.4 / 12 * 10 to the power 3 So this value comes to you as 200 Because it will be cut off by this, so 0.2 by this Once done, the value here is 200 ohms.

[00:29:33]So the option will show you in seconds. Next Question number 15 The Closed and Open Pipes Have the Same Length when they are vibrating simultaneously in Second overtone closed and open see first Let us write about F Close here.

[00:29:55]If we talk about nv / 4l and f open then nv / 2l here the odd multiples are 1 3 5 7 9 So here if this second overtone If it is said then this is the first overtone and this is the second overtone then the second overtone has this value will be five 5v divided by 4l length same It was said. Talk here in second overtones So here 1 2 3 4 and so on. So if this If it is the first overtone then it is in the second overtone You will find three here. So write this as 3v / 2L This much was known from the first introduction.

[00:30:31]Produces six beads. give me this second line It is kept. So here we know its base Less, its base is more then this value is more will be. That is, when these two are differentiated Only then will you get the number of beads.

[00:30:42]That is 3V / 2L - 5V / 4L so this is the value 6 equals 4L you took the LCM so this Value shown is 6V - 4V that is V / 4L So equation number here is equal to one.

[00:30:58]Let's write it down. 6 = V / 4L equation number one I wrote it down. Move ahead. the length of the open pipe is made 3/4 and the close pipe is made to Times of the Original. Now the length of this If changed, the frequency will change. date number Of beads produced in fundamental. Now Asking in fundamentals. So look at what New here the frequency will be FC.

[00:31:20]Fundamentally speaking, the value of n becomes one.

[00:31:22]We are writing this as v / 4 and its length as It has been doubled in the close so 12 so this is Gaya v/8 and while for open ones In fundamentals, the value of n is one or v.

[00:31:35]And here it is saying 2 * length value So this is equal to 3/4 of l and If written correctly, it comes to 2v / 3l because This will be cut off by this so two goes up so 2v / 3l then asked here the number of beads What will happen? So the difference between the two The difference in frequency will tell the number of Equal to beads. So again take the difference.

[00:31:59]You have got this value 2v / 3l - v / 8L so look at its values ​​here Let's solve it. such as these values If you got it, you could write 8 * from here Multiplied by 3, it equals 24 * l If this is cut from three then this becomes 16V and this You have -3v that is 13V / 24L You got the value from here. This is the number of buds. Asking what will happen?

[00:32:29]But if we talk about v/l then see this 24 is equal to. So from here from one to put Can do. That is f' - fc' = 13 / 24 and the value of v / l also came to 24. So What is the result left? 13 So your option is shown.

[00:32:47]First here.

[00:32:50]Next Question number 16 An object is placed at a distance of 2.4 meters from a screen and a convex The lens is interposed between them. That is, the middle I got a convex lens here.

[00:33:09]Whose focal length is assumed to be F. it The screen is the screen. And here it is is the object. object if this is here So let's take it as O. whichever is between these two The separation is said to be 2.4 meters.

[00:33:22]Equal. So let's assume from here that of this object from the optical center The position is u. So here its position image The form will be on the screen and the screen But there is always a real image form. So We will use this concept here.

[00:33:38]Its distance here is assumed to be equal to v.

[00:33:40]Is. The Magnificence produced is five.

[00:33:42]The focal length of the lens is asked. See First of all, since you have entered these values ​​here I mentioned it. This is the direction of incident light because object here There is a place. All distances are divided into optical centers.

[00:33:54]Major from. So U became negative. V It became positive. So given the question Give the value of according to -u + V You have an equation number equal to 2.4.

[00:34:04]I wrote this as one. know magnification Are. So m = in case of here the lens would be is v/u but since real image is formed and real You know it is inverted. So this value you have equals -5. Then the value of v I got it from here -5u, put it in one In. As soon as these -u and these were put in the forest -5u combined to become - 6u = 2.4 of u The value has arrived, pay attention. The value of u You got minus 0.4 Like if the result here is negative then it has been asked that What will be the value of focal length then f/f+ u Just with transverse magnification The value of m using the formula is -5 focal If you want to know the length then the value of f u comes If we cross multiply minus 0.4 then -5f And plus this will become 5 * 4 = 20 so here Pay to save because 0.4 is = f here this If we cover the transfer, then this comes to 6f = 2, so f The value of f is 2/6 that is 1/3 so f The value of came out to be 0.33 Meter then you will see the option here on three Next Question number 17 Two blocks and two of masses 15 kg and 20 kg are placed in contact with each other Rest on a rough horizontal surface as shown in The figure. the coefficient of friction between the blocks and the surface is 0.3 i.e. here The value of μ is stated. So here 0.3 Not defined. So this will be μS.

[00:35:44]This will be μk. A horizontal frame of 400 Newton is applied to a block A the Acceleration of the system. The system has spoken.

[00:35:50]So this means applying this force So this entire system moves together Will start doing it. Like start moving here If done, then in its opposition there is a kinetic Friction will be produced. If this is applied If you have force f then we know Here from Newton's second law from Newton's second law can be written as f - fk = ma Equal to. Whereas if we talk about fk then this is will be μk * n μk given here 0.3 n What will be the value of here? m1+ m2 that this system became * g equals that This is 0.3 mass given here as 15 + 25 * g If the value of is 10 then this becomes 3 * this becomes 10 goes here, this is equal to 40.

[00:36:35]So this comes to you as a value of 120.

[00:36:38]If you get 120 then put it here, then 400 - 120 = 25 and + 15 will make total mass here again This is equal to 40 * a right here.

[00:36:49]If you see the value, it's zero, so here it's eight.

[00:36:51]saved and this is over here three over here one So this is equal to 280 = 40 * a.

[00:36:58]If this is subtracted then the value of a becomes 7 Second square on meter then option shown You will get a second here.

[00:37:06]Next Question number 18 The number of deBroglie wavelengths contained in the Third Bohr Orbit of Hydrogen Atom Ask What is the value of this? See If we look at Bohr's atomic theory here, Let's talk about this deBroglie wavelength.

[00:37:30]Sorry, let's write lambda equal to here.

[00:37:32]h / p = lambda so from here lambda will B equal to h / mv and here Know about Bohr's atomic model So we know that l = mv * r = nh / 2pi Here it is said that third orbit is in place of n.

[00:37:50]Pay will be put here and the value of mv From here mv becomes equal to h / lambda.

[00:37:55]So let's write h / lambda into here.

[00:37:58]If r = 3 / 2π then cut h from h Went. So from here you got the result that is 2ai = 3 laλ which is equal to n lambda Is. And here this value is coming to me is 3 lambda. So what are you asking here?

[00:38:16]Pay? The number of de Broglie wavelengths. So How much before the wavelength value Have you arrived? Three. So how much did you get here?

[00:38:22]Option Four Next Question number 19 Two moles of an ideal gas at STP Subjected to a reversible adiabatic Expansion to triple its volume Magnitude of change in asked change in What will happen to the internal energy? While gamma You have been mentioned equals 1.5. So Know about adiabatic process The relation between temperature and volume He can write like this, will be constant. So From here the result came to you t2 / t1 will be equal to or t1 / t2 So that when we write the reverse relation here, This result will come t1 / t2 will be equal to the power of v2 / v1 is gamma - 1 are in equal inverse ratio. then write like this You can. So look here at t1 / t2 Will be equal to this v2 said here Pe three times ho gaya hai na triple it's The volume is 3v divided by v.

[00:39:26]And this is 1.5 - 1, so that's 3 to the power.

[00:39:30]5 which can also be written here as 3 ki ^ 1 / 2 Are. That is, the value of t2 obtained is t1 / 3 is done and t1 is said to be on STp. So Do you know how much value this will have? that Is 273 Bye isn't it 273 bye The value of 3 came. Like this value was found So delta u know that is ncv * delta t which can be written as n times of r/gamma - 1 * delta t that is t2 - t1 equals that is t1 - t2 Are. So these values ​​you have number of How much is moles? 2 This gives the value of r as 8.34 Write. If the value of gamma is 1.5 - 1 here If we are writing the difference in temperature, then t2 is You will have 273, this will become 273 - 273 / 3 You have got these values. Isn't it? This We will write t1 - t2 here. This result is yours Came closer. Now solve it. to solve So you got this value 2 * 8.34 / 0.5 You got this 273 1 - 1 / 3 Its value is 1.73/2 / 3 We will solve it like this here. Solve The result you got after doing this was 38 will appear equal to 3835 joules. So the option came You have a first here.

[00:41:02]Next Question No. 20 A Magnetizing Field of two 25500 amperes per meter produces Flux of 4 * 10 to the power -5 Weber in the iron Bar of a cross sectional area of ​​0.4 Centimeter Square the Relative Permeability Of the Iron Bar. Look, we know Here magnetizing for any medium Talking about the field, h = b/μ.

[00:41:31]That is, the value of μ of b will be From here you will get the result.

[00:41:36]= That is equal to b / h so like here If you get b/h then find out the values ​​here Will take. So look here – do you know what happens?

[00:41:45]What is? That is μ0 * μ relative = b and b From here the flux will be divided equally By area * h because fluxes are known b * is equal to a. putting in values Let's take it. where the value of flux comes from So the values ​​of flux are given earlier You have 4 * 10 to the power in the question 5 I have written it like this, divided by this is given The area is 0.4 cm², so write -4.

[00:42:13]The value of h given in the question is 2500 You have received these values ​​2500 And here we also know the value of μ knot.

[00:42:22]That is, this is 4π * 10 to the power -7 So, we will know the relative from here.

[00:42:28]What will be the value of μ relative to that?

[00:42:30]So you see, from here it becomes 10 power.

[00:42:32]-7 here it is cut from this so minus 2 left, four to four cut, then μr's See what value of μr you have left.

[00:42:41]Look at the value, two zeros are cut off from this also.

[00:42:42]If you take it upstairs, you have it.

[00:42:45]10 to the power 2ed by 25 * 4 If it is 100 then you are left with 10 here.

[00:42:51]If this comes down after multiplying then this The value you get is 3.14 And with 10 to the power -2, we'll do this If we move it up, it becomes 10.

[00:43:02]to the power 100 but one is cut off So here it shows 1000 / 3.14 if you pay attention So, 3.14 is 30 times If it goes to 90 then you will see only one option.

[00:43:14]There are three here, so you can directly go from here.

[00:43:16]Could have ticked equal to 318 then option I show you three here Next Question No. 21 A satellite of mass 800 kg orbits the Earth at a height of 800 Km From its surface. The Kinetic What will be the energy of the satellite? If the mass The radius of the Earth is given. i.e This means there is a satellite around it.

[00:43:42]revolving in a way whose kinetic Energy is asking what will happen? So near it Let V be the orbital speed. This is given by R. So I have given you this M equal to H. So If it is written directly here then we will know Formula of kinetic energy. that is gmm / 2 * This will be equal to r + h values Let's put it. 6.67 10 to the power -1 Universal gang is constant here This G is the gravitational constant mass of the Meaning given is 6 * 10 to the power 24 * The mass of the satellite in question is given 800 kg, so write it as 800 divided by 2 times this is 6.4 and this gives the value of h You have been kept 800 km, so he too Let us convert it into meters.

[00:44:27]This value comes to you 6.4 * 10 to the power 6 meter plus this will become 800 * 10 to the Power 3, you will have this in your meter. These You have to put all the values ​​here.

[00:44:39]Is. Have to solve it. So after solving The result that will come to you is 2.22 * 10 to the power equals 10 joules. So Your option will be shown here in seconds.

[00:44:50]Next.

[00:44:59]Next question. Question Question Number It is 22. Young's double slit experiment, one of The slit is wider than the other. So that the The amplitude of the light from one slit is Triple that from the other slit. Do you know intensity proportional to amplitude Square. If here the intensity i1 / i2 If we write it then this will become the hole of a1 / a2 Square. If its amplitude is a then Its amplitude tripled according to Two questions. So this value comes to 1/9.

[00:45:25]The value of i2 is shown to be equal to 9i1.

[00:45:29]If IM is the maximum intensity, then Resultant intensity when they interfere at Fuzz difference is given by so this I1 we People here have a new name I don't believe in.

[00:45:42]Let's take it. So this is the value of I2. Chucky If we talk about I Max then I Max is here I am writing via IM. Know the formula What happens to I Max?

[00:45:52]1 + Square of 2 so put the values ​​from here So I'm here for you, under the road, this is the not and this will be you have 9i not so 3 can't write ka whole square that is This is done 4 Whole square of 0 that is equal to 16 knots So you found out the value of IM, that is I not Find out the value of that is IM / 16.

[00:46:20]I also wrote this according to the second edition.

[00:46:23]Resultant intensity when they interfere at Fuzz difference fi now asked that resultant What will be the intensity? then IR will be equal To do that, the formula used is i1 + i2 + 2 I1 I2 * cos if is the fuzz difference here The value of i1 is considered to be i not. + i2 here Pay proofed. So 9i is equal to knots + 2 this will become i not and this will become 9i Not I not I not and here three come and this You will get six because i2 has become 3 9i Note Which we can write as three and root If the root cut looked like this then cos fi came So rewriting the value of IR, this value Done 10i knots + these 6 knots * cos cos Give it in terms of squares, not in terms of If it is placed then use trigonometry here What result came, came 10i not + 6i not is this We can write cos cos that is 2 cos² / 2 - 1 From the formula that is it comes to 10i not plus this is 12i not multiply by giving cos² 5/2 - 6i not these values If you do 10 - 6 then 4 is not common here If you take it then this result is left with you 1 Plus this is 3 cos² / 2 of I knot The value can be written in terms of IM which is Given IR = 4 I know the value of not In terms of IM, it is IM/16 times 1 + 3 cos² 5 / 2 is subtracted from this IM/4 = 1 + 3 cos² / 2 So you will see the option here Pay Four Next Question number 23 to solid sphere s1 and s2 of same uniform density fall from Rest under gravity in a viscous medium and after some time reach terminal velocities v1 and v2 respectively the ratio of If the masses m1 / m2 are 27 then what will be v1 / v2?

[00:48:36]So the first formula for terminal velocity is that Is 2 / 9 times of r² g rho - σ / nit means terminal velocity proportional to here It is given in proportion to r² is the square of the radius, so write the radius here.

[00:48:53]Pay pata kar lenge that is v1 / v2 will be equal to r1 / r2 times the square of this So the answer is mass equals density * Volume is said to be m1 / m2 of material Uniform Density So Cut Ho Gaya Volume 4 / 3 πr then r1 / r2 This value is given to you, it is 27 27 From here r1 / r2 can be written as 3 to the power of 1/3 so this is three because 27 is cubic, here you will find three As soon as this value here comes to three, put here that is 3 square so this If the value becomes 9 then you will see the option here.

[00:49:32]per second Next Next question question number 24 four Metallic plates are charged as shown in the figure Now Match the Following Two Columns Know There are metallic plates at some distance here If separated, it behaves as a sheet Due to which we can write the electric field are sigma by 2 0 due to sheet Talking about point one, for the one If this forest is here then the electric field Let's call it this forest, it's near us.

[00:50:03]Two, these are three plates which behave will age a here because of infinite sheet From. If the separation between its If the dimension is less than then it is charged by one The electric field came in this direction.

[00:50:14]moved radially outward to here because And I came here because of Three. This portion It was first. So E first type will be equal So this will be E2 - E1 - E3 equal to E2 You have the value of. Give the value of E2 It is kept for two. That is 4 / 2 0 It will be sigma of minus that is 2/20 - 2/20 If all this is cut then the result is zero.

[00:50:47]Here a should be equal to s.

[00:50:50]Should be. So the a of is shown here s next Let's grow. Here we talk about the second portion If you did it here, you would have seen it on the second one.

[00:50:56]Are. This position is second. within seconds The electric field is on the left side. his Because of this E1 happened. is negative then radially If it is inward then write E2. Because of this Electric field comes to you E3 so E I am writing on the second. That is second pay E1 + E2 and this minus E3 due to E1 to Sigma by two no plus this will become four sigma by 2 0 remember the minus sign here I am not applying it because the direction is here been defined so here pay with Polarity is putting and - by E3 It's here 2 / 2 0 This one is cut off, this one is cut off When the cut happened, the position of the second one came that That is 2 / 0, which means whatever happens on the second will be aa.

[00:51:45]If you have P equal to this, then this becomes P So A's S is visible, so A's S is done and B What happened, P, I saw this. like this here If you find out in the third, look for the third.

[00:51:58]I am writing this here. This is three electric field two here at three went radially inward because of. And here radially outward here because of three Went. And because of the forest, this time I got it like this To you. So this is writing on position three.

[00:52:13]So E3 pay will be equal to E1 - E2 - E3 Writing equals E due to one. That Is 2 sigma by 2 0 minus that is 2 sigma by 2 0 - 4 / 2 0 so this value comes out to be -2 /0 So you see C equals R here now.

[00:52:38]Let's check it. A's S's B's P's C's Here R, let's see which option is shown.

[00:52:44]Are. See Yes A ka SB ka PC ka R to option I show you three here Next Question No. 25 The power of a water pump is 6 kilowatts if g 10 meters per second square The amount of water in litre it can be stored in 2 liters.

[00:53:07]minute at a height of 20 meters know the power work done divided by Time that is it will be mg gh/t equals and mass can be written as density * Volume * g * h/t put all the values Are giving. This value is 6 * 10 ^ 3 Finding the Density of Water (10^3 Volume) Is. The value of g is 10, the value of h is 20 and I have given him 2 minutes time in this Converted it. This is cut off from this. These This made the cut. This is cut off from this. So 10 left here. Isn't it? 10 left. So here Pay volume ka value aa gaya v equal to this Done 36 / 10 That is 3.6 meters If we want to write this in litres then volume v = 3.6 Multiply 10 to the power by 3 If you take it then it comes to 3600 You can see the option equivalent to liters here.

[00:54:03]First Next Question number 26 of 26: A long statement Wire carrying current of six 60 amperes Rest on a table another wire AB of length 2 meter mass 4 kg carries the same current but in Opposite Direction The Wire AB is free to Slide up and down the height up to which AB Will Rise. So look here it is saying That if this is a pay table here. a long State wire carrying current 60 amperes Rest on a table. So let's assume here Its current is 60 amperes.

[00:54:40]And at what height from here is this Let's take this similar wire AB for you.

[00:54:46]pass in which the current is in the opposite direction It is flowing and the same current is flowing here.

[00:54:51]So this value is also given to you, I2, this also Its mass is given as 60 amperes.

[00:54:57]So if the mass is mg then we would assume this height.

[00:54:59]How much will it rise equal to H?

[00:55:01]has been asked. If you look here, it If the current is in the opposite direction, the force Here nature is repulsive. know that Are. This is the balance in equilibrium will calculate its weight mg which is μ0 equal to i1i2 * l / 2d = mg value of μ0 Put 4π * 10 to the power -7, the current is 60 * 60 And the length of the wire is given. that is 2 meter by this 2π and the value of d here is h Mass given in the question that is a 4 grams so 4 * 10 to the power -3 write g If you write the value 10, then from here pi to pi It's been cut from two, let's cut it to 10 To the power of -7 is -7 from here it is cut If we cut minus 5 here, we will be left with minus Now if Pay To is saved here then from here h Solve the values ​​and you will get the result.

[00:55:56]pass h equal to this got got 4 * 36 * 10 to the power this is left -5 by this is 4 * 10 to the power -2 this is cut off by this If you get -3 then it will come to 3.6 centimeters So you see the option here Pay Four Next Question No. 27 A road of weight w/2 is Supported by two parallel knife edge A ends B and is in equilibrium in a Horizontal position. Let's make it first. Two Here are the knife edges. A and B gave it a name A gave it a name B so its Its normal reaction NB Its normal Reaction NA its weight from the center of mass It must be W/2, I wrote it like this earlier. First The Nice Are at a Distance from InformationNation of 2D These two are at a distance of 2D from each other Are. It is written like this, each other the center of mass of the road is at a distance of X from A The center of mass is at a distance X. So This distance from here will be 2D - X.

[00:57:05]Normal reactions of A are RA and RB. Let go It was called RA RB. Then write RA and RB Let's take the values ​​here. Giving RA / RB What will happen, he asked? first here Talking about translational equilibrium The value of ra + rb is equal to w/2 equivalent equation number one for rotational Torque for equilibrium is about the same If you consider, you have it here What results did you see for rotational ya?

[00:57:31]translation equilibrium or rotational equilibrium Writing Equilibrium So That Is w/ 2 * x will be equal to this will be rb * equal to 2d so you get the values ​​from here That is W/2 will be equal to RB * 2D / X Let's put it in the forest. put in Like put it in the forest, see what Did you get it? The value of RA + RB = W / 2 is Equal to 2D / X * RB. So from here RA Equal to Aa Gaya that is 2D / X - 1 * RB K Equal. Asked what will happen to RA/RB?

[00:58:14]That is 2D - X / X will appear. then show the option You got 2D - X / X here. So the option I showed you four here.

[00:58:25]Next Question number 28 in an experiment the Angles are required to be measured using An instrument with 39 divisions of the main scale Exactly consider with the 40 divisor 40 Divisions of the Vernier scale. If the smallest Division of the main scale is 0.4° than the least Count of the instrument. See here If MSD is 39 off then consider 40 off From VSD then find out 1 MSD from here Will take or 1 VSD will be detected. that is This will be equivalent to 39/4 of MSD If asked for the least count, you know 1 MSD - equal to 1 VSD, then this value You will get 140 * equivalent to MSD The value of MSD is given as 0.4° Divided by this is 40 and we know People here there are 60 minutes in 1° and 1 1/60° in a minute If you know what happens then how much is there in 0.4° Will it be done in a minute? So here from 60 If we multiply it then it gets deducted from this.

[00:59:34]This comes to you in the equivalent of 0.6 minutes. So You will see the option here first. Next Question number 29. Assume that the Molecules are moving with the root mean Square speed at a temperature of 400 Calvin. The DeBogli Wavelength of Nitrogen molecule is while the atomic mass of the Nitrogen is given in the question, that is You have 14 atomic mass units so lambda We know that it is equal to h/mv which can be written as are h / under root 3mbt We know this formula, so Lambda = value of h is 6.63 10 to the Power -34 / 3 nitrogen molecules here It has been said and the atom has been given, so 2 * 14 But we will write it in atomic mass units.

[01:00:29]If we convert this into kg then it is 1.66 10 to the power -27 so this is converted into kg The value of the Boltzmann constant given is 1.38 10 to the power -23 and give you the temperature is placed in the question equal to 400 Kelvin When we put its values ​​here If you solve it by putting then you will get the result Aa Jayega That is 2 39 * 10 to the power power -1 meter, you will see the option here Four.

[01:00:59]Next Question No. 30 A Neutron Colloids Head on with tritrium at rest.

[01:01:14]what fraction of the neutron's energy Would it be transferred to the tritrium?

[01:01:18]Look directly, we remember here.

[01:01:20]If we talk about the formula, then This is tritrium here, so three times Here it is at rest so loss in kinetic How much energy is transferred will go to those who talk in the form of loss If so, 4m1 m2 / m1 + m2 square in case of collision, so here if the neutron If the mass is m then the mass of tritium will be 3 times of mk that is m + 3m² So from here 4 * 3 * m² / this is 16m² cut Went. This is cut off from this. So this value comes I asked you about 3/4 percent, so Delta k / k will be equal to 3/4 * 100 so the value will be If it reaches 75% then you will see the option here for second Next Question number 31 Two capacitors for Micro Ferrule Six Micro Ferrule R Individually Charged Across a 12 Volt Battery initially charged here Pay. Look, this is the first one and this one right here Second, it was charged. charged When it goes, it gets C2 V2 charge.

[01:02:32]will go to C1 V1 give all the values ​​here It is kept. After Being Disconnected From the Battery they are connected together with the Attach the negative plate of one to the positive plate.

[01:02:41]Plate. That means if this is positive here Negative so its negative than positive Connected here. This way It was connected like this. Attach to Positive Observe what is the final total energy Sturd. Like here you connect it If you do this, common potential will emerge. First common We will find out the potential. Then V = any one One charge is positive and the other is negative.

[01:03:04]Will write. Because here the polarity is opposite Connected. Hence the common potential I will write Q1 - Q2 instead of Q1 + Q2. Who that is you have C1V1 - C2V2 / C1 + C2 C1 The value of you have is 4 and this here The value given to you is equal to 12 and Whereas here he has given six to someone Let us assume one thing here that this If a larger value has been given to it, then we Let's say this is equal to six and this If you have a value equal to four, then this 6 - 4 wrote 12 took the common from here and this You've got 6 + 4 micro ferrets equal so from here this is left for you this two Done * 12 and this is what you have 10 so This comes to 2.4 volts. This is V's You got the value. asked what the final total was What will happen to the energy? So U final equal to total capacity that is C1 + C2 * bi Common Potential. So half half this is 10 * 10 to the power of -6 added to 6 + 4 In the micro ferret. And this value is yours The result is 2.4 * 2.4. As soon as its If you solve the value then this value will be yours It comes out to be 28.8 * 10 to the power -6 joules.

[01:04:16]So your option is shown here as three.

[01:04:19]Next Question number 32.

[01:04:30]The Volume of an Metal Sphere Is Increased by 0.36% when its temperature is raised By 60° Celsius. The Coefficient of Linear Expansion of the Metal. Look, we know When people talk about deltaV, they can write v * gamma * delta theta where gamma is What is it called? cubic coefficient of Expansion. In this, deltaV / v equal to can be written as gamma * delta theta. These The value given to you in percentage is 0.36 / 100 also written Gamma. And this temperature How much are you raising? 60° then write 60 Let's take it. So look at this from here, Gamma's Value aa gaya that is 36 / 10 to the power brought down so 4 into I wrote this 60 and it came out to be 6 * 10 to the Power on -5°C. So here is the answer Pay Agar Question Mention Hota Coefficient Of Volume expansion is your option three.

[01:05:22]Would. But if we ask for linear, then gamma is equal to Know 3 Alpha. So alpha equals two If you write gamma / 3 then accordingly you have The answer will be 6 * 10 to the power -5 / 2 that is 3 * 10 to the power -5 in degrees Celsius So here if instead of linear we have given If there is cubicle expansion then the option is yours Here we get three but it is linear.

[01:05:45]The answer will come next Question No. 33 In a Half Wave Rectifier Circuit operating from 60 Hz mains frequency the fundamental frequency in the Ril will be see know that half wave Only one diode is used in the rectifier for rectification for rectification One diode for which the input here Only half of the frequency is used here We do. Half blocks. Half Pass He gets it done here. So the frequency of The output will be equal to the input Will go. Whereas in full wave rectifier There are both positive and negative cycles here.

[01:06:25]If it does rectification then it should be two times goes. If I asked for a full wave, then 120 half If you ask, you will see the option here.

[01:06:32]Seconds. Next Question No. 34 A disc rotates so that Its angular acceleration alpha is given as alpha = minus given alpha = -e.g. Power 1/3 which can be written as domeg / dt If the initial velocity of the disc is 8 radian per second is the time taken by the disk To stop and see what you can write about it.

[01:06:59]domeg / omeg = 1/3 of ^ - dt cross Multiply it and then write it here like this Bring up the power and write it like this dt Integrate both sides when t equals In the initial it is given that this value Initially when t = 0 then this value will give you Given that 8 t is equal to when t is reached then this stops It's done, it's stopped, you know here The formula for x^n gives the value of omega equal to 1.

[01:07:26]/ 3 + 1 / 1 / 3 + 1 and this value here 8 to 0 and this value becomes equal to - t.

[01:07:35]So did you see this from here? Omega Key Power is 2 / 3 / 2 / 3, limit is 8 Since 0 = -t, we can write 0 - 8.

[01:07:47]to the power of 2 / 3 = -2 / 3 * 10 what is there cube of 2 cube of 2 If you write it, it will become three cuts and then four Will be saved. If minus is deducted from minus then this is 4 = 2 / 3 * 10 so t equals 6 Second, you will see the option four Next Question number 35 A step-down transformer converts Transmission line voltage from 33000 to 220 volts the primary of the transformer has 12,000 tons and efficiency of the Transformer is less than 90% of the output power Is 45kW than the input power. See Let's talk in terms of efficiency So what would this be? Output upon input power.

[01:08:36]Output upon then asked this time about input What will happen to the power? So this P output Divided by efficiency gives output power I have kept 45 kg. So 10 to the power 3 W Whereas the efficiency is 90%, then it should be written as For. So from here it's cut off from this. So this You have got the equivalent of 50 kilowatts. So You will see the option here in seconds. Next Question No. 36 A bob of heavy mass M is Suspended by a light string of length L The bob is given a horizontal velocity V Not as shown in the figure. If the string Gets Lack at Some Point P Making N N N n n n n n n Angle of 30° from the horizontal the ratio of the speed V of the Bob at a point P to its initial speed V If not here, tell its speed here.

[01:09:26]If the value is V then what is its ratio Will you go? So let us know. See here if Talking about it, you got it mg if here If we talk about the component of mg here and Along with tension and plus one mg of If you look at the component separately, you would have seen it like this Are. This came to you in the equivalent of mg. it Here it is given 30°. This is the tension here t came and plus one here got the speed v To you. If this mass is m then it has a The component will come to 30. This 90 this 60 so this Again it became 30. that is mg cos 30 but You will get mgsin 30 towards the center. So In the first case, we know If you want centripetal force then t + mg sin theta will be equal to mv² / r r here If I slack off evenly, there is zero tension here.

[01:10:14]So the value of v² that we get from here is Let's write down glsin theta equation number one Are. Then here he is asking about the speed What will happen? So look from here Kinetic energy was used.

[01:10:26]Conservation of energy from CO₂ conservation of energy then K at A + U at A = K at B + UB Kinetic Energy at A written as 1/2 MVO² This became zero. Kinetic energy at B aa 1/2 MV² + now write here that reference So mgh H is going over here look at This is it and this factor if we look here If you look carefully, what is this value equal to?

[01:10:54]Will he come? If this length is l then l sin 30 so You will find this here, lsin equals 30° So you get l + l sin 30°, write it like this So, like we solved it here.

[01:11:09]Look mmm the cut kept happening v not squared here v² + 2g of l The value here is common, so I wrote 1 plus this.

[01:11:18]Putting in the value of 1/2 sin 30 And from here you could also put v² = g * The value of l * sin 30 is given by 1/2 theta To you. So as soon as this is solved, this comes You have 3/2 here 3/2 to two cut Once done, you get the result v² + 2 When cut to this, the value of 3gl v² is shown.

[01:11:40]If you put it here, you will see this value.

[01:11:42]v² here this will become three, that is is gl / 2 + 3gl cross multiply by Gaya 7gle / 2 here comes v not square of both If the ratio is asked here, then put the ratio giving v² / v not square so this The value becomes gl / 2 and this comes to 7gl By 2, the remainder is 1/7 of both here.

[01:12:09]If the ratio is asked then it will be 1 / 1 7 So you will see the option here first.

[01:12:17]Next Question number 37 A square loop of side 8 cm.

[01:12:29]Resistance 0.4 ohm is placed vertically in The East West Plain. The Uniform Magnetic field of 0.2 Tesla set up Across the plane in the north-east direction.

[01:12:38]That means there is something like this here. This is magnetic The field is in the North East direction The value given is 0.2 Tesla. one here There is a square which is placed like this East And along the west. So this is East. These It got wasted. This is the north. This South Done. It was said here that North East If it is a plane then the angle here will be 45° so this will also be 45° flux know b * a * cos theta so the first information from here it I understood and wrote down the value of this flux.

[01:13:08]The magnetic field has decreased to Zero in 0.4 seconds at steady rate Magnitude of current has been asked. So if If we talk about E here, what is E?

[01:13:18]Will you go? d / dt and this is where we talk about current then the current will become e / a that is di / dt times the 1/r current asked for Putting in the values. So here di / Talking about dt, what is this result?

[01:13:33]Will it go to you? That is a * cos here 2 And this will give db/dt so i = 1/r*this Let's write down a / 2 * db / dt values ​​arrived at you have i = 1 / r a / 2 db / dt all values ​​given Is. put all the values ​​here do. Let's solve it by putting. 1 / The value of r r is given as 0.4 and this 2 also here area side square which That here the square loop is given, so this will become 8 * 8 * 10 to the power of -4 and db Here the current is given in volts.

[01:14:10]It takes 0.2 seconds for the magnetic field to change The time is 0.4 seconds from here so see if Solve this here, so this is from this When the cut is done, this value becomes equal to two.

[01:14:19]Here this will be cut from two to four, so this The value you get after solving is 5.66 6 10 to the power equals -3 amperes. So You have the option here, sorry, this option It had direction. Then I showed you the option First here. So here you can directly You could see the option here first Will go. What is Reason? Because here it is At now, there is value and extra for 2.

[01:14:39]will be. So, the option will appear here.

[01:14:41]First, not second. So the option will be here Pay first. Next.

[01:14:45]Next question. Question number 38. A The rocket is going upwards with accelerated Motion. A man sings in it feels he waits Increase six times your weight if the mass Of the Rockets Including That the Man Is 2 * Power 4 kg How much force is being applied By rocket engine this question was asked here You have to tell me what the values ​​will be. So See what was said here? If your It has this rocket system. This rocket There is exhaust happening here in the system.

[01:15:11]This is a man. He has placed a rocket here.

[01:15:14]Is. So you know that the rocket thrust here Force is applied. And here In opposition to gravity, it feels like going down.

[01:15:21]The one with the F becomes gravity. So the net force Applied by the here these rocket engines By. So what do we write about it?

[01:15:29]That is this is going to be thrust and minus here.

[01:15:31]Pe gravity w. So thrust asked from here Gaya in question. then the thrust will be f Net plus here equals net weight. If If we talk about the man here, then for the man If we look here, its weight is mg.

[01:15:45]There's a normal reaction here and there's a The above is kept in accelerated motion. These Shudo force will be equal to a here. If If it is accelerated motion, then we will write it here.

[01:15:55]log n = m times g + a. And He is saying that the six times here If its weight increases then the value of n will be 6mg m times of g + a m to m cut Once done, you get the value of a from here.

[01:16:10]5g meter per second squared equals 5G has arrived here, so now both have been combined.

[01:16:15]Now that the rocket has been discussed Rocket including the mass that has been given and how much force is applied by the rocket engine so rocket engine which is applying f That is called thrust. Now combine both Are moving through. So m + m * a shows up and The weight of both will be m + m * g Equal. That is, now we will see the effect of both.

[01:16:36]That is g + a that is what you asked How much force is generated by the rocket engine?

[01:16:42]There will be exertion. Give the combined mass of these two The question is 2 * 10 to the power 4 Write g here and also give its value.

[01:16:51]Here it is combined to the tune of 5g.

[01:16:53]If it reaches 6g, then this is the thrust force here.

[01:16:56]Its value has come, that is 6 * the value of g 2 * here 2 * 10 to the power 4 so this The value you get is 12 * 10 to the power 5 Newton so you see the option here seconds Next Question number 39 Column Base Queries Purely Capacitive We know the circuit here first.

[01:17:24]If we talk about the fuzz diagram here, then the current The voltage across the x-axis Resistance Voltage Across Inductor Voltage Across Capacitor In Inductor Voltage leads current in capacitor If voltage lags current then purely If the voltage lags behind the capacitive current Here I showed you P of A purely It is an inductive circuit. Purely inductive to The voltage leads here. Then S Done. LCR Resonance Resonance XL = XC done. So Z came only after R Equal. So you saw this in the same fuzz. This is it Went. LCR circuit shows you the value of R Equal. So A has P, B has S and C has Q. of A Let's see P. P of A, S of B and Q of C.

[01:18:09]So you saw option three here.

[01:18:12]Next Question number 40 The power of a motor is 600 W If the unit of length is double that of the mass Mass is half and that of the time that time of Time is above tripled the power of the motor In the New System of New Units. Know Yes, we are the product of n*u.

[01:18:37]Constant containing numeric value int unit. So here we can write n1u1 = that is equal to n2u2. Then the value of n2 is will go to n1 times u1 / u2 that is n1 The value given in the question is 600.

[01:18:52]went m and here this month is said that month If it is halved then m / 2 and If there is power here, then we know about power.

[01:19:01]Dimension ml² t - c So here comes one.

[01:19:04]Talking about length, what is length?

[01:19:06]Here? The length is doubled. So if this If it is l then it will become 2L or hole here square times this is t so its time If it is tripled then write -3 here.

[01:19:18]This value has come to 600, this too shows this value.

[01:19:21]This is 1/4, this becomes 27 when it is minus So when you solve this, you get this two So this is 300 * 27, so this comes to 81 Equally, the option is shown here, three Next Question No. 41 in Young's Double Slit Experiment the distance d between the Slits S1 and S2 are given by D.

[01:19:54]He has given the question equal to 2 mm.

[01:19:56]In. what should be the width of the each slit B shows as to obtain at maxima of the double Slit pattern. et maxima in the double slit and central maxima of the single slit.

[01:20:06]There is a single slit. So we understood that this Diffraction is a phenomenon. For Maxima We write n lambda de means n lambda d / d then the value of n at Lambda here d / d Central bra here The fringe that forms on them is considered single.

[01:20:21]In Slate, that's two times lambda.

[01:20:23]dead by its small a suppose bda d cut It's done, this is cut, it's four, so a Now you have the value of d / 4, that is 2 / 4 That's what you got equals 0.5 mm So you will see the option here first.

[01:20:40]Next Question No. 42 A wall is made of equal Thick layers A and B of different materials Thermal conductivity of A is three times that of B In the steady state the temperature difference Across the wall is 60° Celsius. The Temperature Difference Across the Layer. See one here There is a wall. Like these walls accept it. Here you have a layer of material A, a of material B. So if its temperature here We are writing it down, it is theta. Its Temperature theta is also of this junction Temperature theta. You know, steady here.

[01:21:15]The heat flow in the state should be the same Will go. That is h1 = h2 equal to the rate of Flow of heat. It is said here three times a * we will write this as θ a - equal to θ / l. whereas if its k is According to the question asked, this should happen will be θ - θB / l. All these values ​​are for you.

[01:21:37]If you get passed from here then you will get the result.

[01:21:40]Show that 3 theta is equal to θ - 3 theta = θ - θB so This is equal to 3 theta + θB = 4 theta The question said the temperature The difference across the walls is 60 centimeters Meaning θ - θB gives you 60 cm. And He is asking you, so what should we do?

[01:22:06]Here? Look, write these values ​​here.

[01:22:08]Have been. 4theta Why is it arranged so that + θB = 4 theta and + θ Did you? Because look at the values ​​from here Have to find out. If we add θ theta to both sides, 4 theta will come here. transferred it here So I bought four common ones. θ a - theta equal to Transferred it here. θa - θb and that is have given you the equivalent of 60° Celsius and θ a - theta value comes out to be 60° / 4 that If you get this option then it is 15° Celsius.

[01:22:40]I asked about the temperature difference That's what you get across a θ a - θ = 15° Celsius Next Question No. 43 The RMS value of the electric field of the light coming from the The sun is 800 Newtons per Coolum. The Average Total Energy Density of the Electromagnetic Wave. So we write the average density.

[01:23:08]1/20 * square of e not so 1/2 its values Putted 8.85 10 to the power -12 E not Here the peak value is given whereas RMS We know the value and what ERMS is.

[01:23:23]That is E not / 2. So from here it You will get the value 800 Hole Square of 2. These values ​​were solved So the result is 5.66 10 to the power -6 joules.

[01:23:36]Per meter energy density. then show the option You are here first.

[01:23:42]Next Question No. 44. A wire stretched between Two rigid supports vibrate in the Fundamental mode with the frequency of 90 Hertz. The mass of the wire is 40 grams and Its linear mass density is 3 * power-2 kg per meter the speed of the transverse wave What will happen? First see and know If we talk about μ, then it is divided into mass You can write the unit length. then the length will come Mass divided by linear mass density. Mass I have given you 40 grams in the question. So Write 10 to the power -3. The value of μ is 3 * 10 to the power -2 This cuts it off. So The value of l is given by you: 4/3 f = to We know that it is nv/2l.

[01:24:29]The fundamentals were told to you. See here Asked is in fundamental mode. then f The value of n is 1v/2l so v will come to you equal to f * 2l The frequency is 90 * 2 * 4 / 3 This is cut from this so this is what you have.

[01:24:49]240 meters per second, then you will see the option three here Next question number 45 A heater coil is rated at 400 watts and 200 volts.

[01:25:02]Let's assume there's a heater coil here.

[01:25:04]Whose resistance will be R, its rating If the power rating voltage is given then first Let's find out this. Rating power is V will not be squared by R then R will be The value is 200/200 by power.

[01:25:18]If 400 is deducted from this then this value will come.

[01:25:20]You have 100 ohms, it is cut.

[01:25:24]Into Identical Parts. like give it If you cut into identical parts, you will see The resistance of one part will be R/2.

[01:25:32]The other part will also have resistance.

[01:25:34]You have R/2 because you made identical cuts.

[01:25:37]You also got this value, 50 ohm.

[01:25:39]Both parts are equal to 50 ohms Connected together in parallel, now take both connected in parallel as soon as If we connect in parallel then R What will be the equivalent of R/2?

[01:25:50]If it is in parallel then it is written R/N So this value comes out to be R/4, two registers are same.

[01:25:55]If it is in parallel then r/n is equal to So here r/2 becomes r/4. R The value of the equivalent has come to you as 100.

[01:26:02]/ 4 That is equal to 50 / 2 = 25 ohms. The Energy Liberated per second in the new Combination if Same Source again be applied i.e. energy liberated means When power was asked then v² / r became 200 It also became 200/25 when this was shown at times This comes out to be equal to 1600 watts or write this down.

[01:26:26]can 1600 joules per second so you have the option Show here on second because on second asked If it is there then its value will be one here.

[01:26:35]1600 joules arrived So this was today's discussion students. now today The same day is exactly one week later, the 21st of June.

[01:26:48]That day is about to be yours again because You have your exam today. As hard work and As well as you have prepared now.

[01:26:55]The time has come to get its result. As You did well in NEET last time also.

[01:27:00]Had performed. the same to you again I have to perform here. your best Have to give. So you go with the work. You relax Solve the question from there. from you It is very good that the question is solved there.

[01:27:11]Going to do. You will get good marks Are. So all the very best for my future Doctors. Thank you so much. All the Very Best.