Other Physics · JEE Main previous year questions

2024 52 questions

1. Q482024 · 4 Apr 2024 · Shift 2

   An electric bulb rated $50\text{ W}-200\text{ V}$ is connected across a $100\text{ V}$ supply. The power dissipation of the bulb is:

   1. A.$100\text{ W}$
   2. B.$50\text{ W}$
   3. C.$12.5\text{ W}$
   4. D.$25\text{ W}$
   Show answer

   Answer: C

2. Q522024 · 1 Feb 2024 · Shift 1· Numerical answer

   A plane is in level flight at constant speed and each of its two wings has an area of $40{\mathrm{m}}^2$. If the speed of the air is $180km/h$ over the lower wing surface and $252km/h$ over the upper wing surface, the mass of the plane is ____ kg. (Take air density to be $1\mathrm{kg}{\mathrm{m}}^{-3}$ and $\mathrm{g}=10\mathrm{m}{\mathrm{s}}^{-2}$ )

   Show answer

   Answer: 9600

3. Q322024 · 1 Feb 2024 · Shift 2

   A body of mass $4\text{ kg}$ experiences two forces ${\vec{F}}_1=5\hat{i}+8\hat{j}+7\hat{k}$ and ${\vec{F}}_2=3\hat{i}-4\hat{j}-3\hat{k}$. The acceleration acting on the body is :

   1. A.$2\hat{i}+\hat{j}+\hat{k}$
   2. B.$4\hat{i}+2\hat{j}+2\hat{k}$
   3. C.$-2\hat{i}-\hat{j}-\hat{k}$
   4. D.$2\hat{i}+3\hat{j}+3\hat{k}$
   Show answer

   Answer: A

4. Q372024 · 1 Feb 2024 · Shift 2

   A big drop is formed by coalescing 1000 small droplets of water. The surface energy will become :

   1. A.$\frac{1}{100}\text{ th}$
   2. B.$\frac{1}{10}\text{ th}$
   3. C.$100\text{ times}$
   4. D.$10\text{ times}$
   Show answer

   Answer: B

5. Q382024 · 1 Feb 2024 · Shift 2

   A cricket player catches a ball of mass $120\text{ g}$ moving with $25\text{ m/s}$ speed. If the catching process is completed in $0.1\text{ s}$ then the magnitude of force exerted by the ball on the hand of player will be (in SI unit) :

   1. A.30
   2. B.24
   3. C.12
   4. D.25
   Show answer

   Answer: A

6. Q352024 · 31 Jan 2024 · Shift 1

   The relation between time '$t$' and distance '$x$' is $t=\alpha x^2+\beta x$, where $\alpha$ and $\beta$ are constants. The relation between acceleration $(a)$ and velocity $(v)$ is :

   1. A.$a=-5\alpha v^5$
   2. B.$a=-3\alpha v^2$
   3. C.$a=-2\alpha v^3$
   4. D.$a=-4\alpha v^4$
   Show answer

   Answer: C

7. Q372024 · 31 Jan 2024 · Shift 1

   The parameter that remains the same for molecules of all gases at a given temperature is :

   1. A.kinetic energy
   2. B.mass
   3. C.momentum
   4. D.speed
   Show answer

   Answer: A

8. Q422024 · 31 Jan 2024 · Shift 1

   If the wavelength of the first member of Lyman series of hydrogen is $\lambda$. The wavelength of the second member will be

   1. A.$\frac{27}{5}\lambda$
   2. B.$\frac{5}{27}\lambda$
   3. C.$\frac{27}{32}\lambda$
   4. D.$\frac{32}{27}\lambda$
   Show answer

   Answer: C

9. Q372024 · 31 Jan 2024 · Shift 2

   If two vectors $\vec{A}$ and $\vec{B}$ having equal magnitude $R$ are inclined at angle $\theta$, then

   1. A.$|\vec{A}+\vec{B}|=2R\cos \left(\frac{\theta }{2}\right)$
   2. B.$|\vec{A}-\vec{B}|=2R\cos \left(\frac{\theta }{2}\right)$
   3. C.$|\vec{A}-\vec{B}|=\sqrt{2}R\sin \left(\frac{\theta }{2}\right)$
   4. D.$|\vec{A}+\vec{B}|=2R\sin \left(\frac{\theta }{2}\right)$
   Show answer

   Answer: A

10. Q382024 · 31 Jan 2024 · Shift 2

    By what percentage will the illumination of the lamp decrease if the current drops by 20%?

    1. A.26%
    2. B.36%
    3. C.46%
    4. D.56%
    Show answer

    Answer: B

11. Q472024 · 31 Jan 2024 · Shift 2

    A body of mass $2\mathrm{kg}$ begins to move under the action of a time dependent force given by $\vec{F}=\left(6t\hat{i}+6t^2\hat{j}\right)N$. The power developed by the force at the time $t$ is given by:

    1. A.$\left(3t^3+6t^5\right)W$
    2. B.$\left(9t^5+6t^3\right)W$
    3. C.$\left(6t^4+9t^5\right)W$
    4. D.$\left(9t^3+6t^5\right)W$
    Show answer

    Answer: D

12. Q412024 · 30 Jan 2024 · Shift 1

    At which temperature is the r.m.s. velocity of a hydrogen molecule equal to that of an oxygen molecule at $47^{\circ }\text{C}$ ?

    1. A.$20\text{ K}$
    2. B.$80\text{ K}$
    3. C.$4\text{ K}$
    4. D.$-73\text{ K}$
    Show answer

    Answer: A

13. Q362024 · 29 Jan 2024 · Shift 1

    At what distance above and below the surface of the earth a body will have same weight. (take radius of earth as $R$.)

    1. A.$\frac{\sqrt{3}R-R}{2}$
    2. B.$\frac{R}{2}$
    3. C.$\frac{\sqrt{5}R-R}{2}$
    4. D.$\sqrt{5}R-R$
    Show answer

    Answer: C

14. Q592024 · 29 Jan 2024 · Shift 1· Numerical answer

    A ball rolls off the top of a stairway with horizontal velocity $u$. The steps are $0.1\text{ m}$ high and $0.1\text{ m}$ wide. The minimum velocity $u$ with which that ball just hits the step 5 of the stairway will be $\sqrt{x}{\text{ ms}}^{-1}$ where $x=$ _______ [use $g=10{\text{ m/s}}^2$ ].

    Show answer

    Answer: 2

15. Q402024 · 29 Jan 2024 · Shift 2

    The temperature of a gas having $2.0\times 10^{25}$ molecules per cubic meter at $1.38\text{ atm}$ (Given, $k=1.38\times 10^{-23}{\text{JK}}^{-1}$) is :

    1. A.$500\text{ K}$
    2. B.$300\text{ K}$
    3. C.$200\text{ K}$
    4. D.$100\text{ K}$
    Show answer

    Answer: A

16. Q442024 · 29 Jan 2024 · Shift 2

    A particle is moving in a straight line. The variation of position '$x$' as a function of time '$t$' is given as $x=(t^3-6t^2+20t+15)m$. The velocity of the body when its acceleration becomes zero is :

    1. A.$6\text{ m/s}$
    2. B.$10\text{ m/s}$
    3. C.$8\text{ m/s}$
    4. D.$4\text{ m/s}$
    Show answer

    Answer: C

17. Q572024 · 29 Jan 2024 · Shift 2· Numerical answer

    Two metallic wires $P$ and $Q$ have same volume and are made up of same material. If their area of cross sections are in the ratio $4:1$ and force $F_1$ is applied to $P$, an extension of $\Delta l$ is produced. The force which is required to produce same extension in $Q$ is ${\mathrm{F}}_2$. The value of $\frac{F_1}{F_2}$ is _________.

    Show answer

    Answer: 16

18. Q312024 · 27 Jan 2024 · Shift 1

    Position of an ant (S in metres) moving in Y-Z plane is given by $S=2t^2\hat{j}+5\hat{k}$ (where $t$ is in second). The magnitude and direction of velocity of the ant at $t=1\text{ s}$ will be :

    1. A.$16\text{ m/s}$ in $y$-direction
    2. B.$4\text{ m/s}$ in $x$-direction
    3. C.$9\text{ m/s}$ in $z$-direction
    4. D.$4\text{ m/s}$ in $y$-direction
    Show answer

    Answer: D

19. Q352024 · 27 Jan 2024 · Shift 1

    The acceleration due to gravity on the surface of earth is $g$. If the diameter of earth reduces to half of its original value and mass remains constant, then acceleration due to gravity on the surface of earth would be :

    1. A.$g/4$
    2. B.$2g$
    3. C.$g/2$
    4. D.$4g$
    Show answer

    Answer: D

20. Q382024 · 27 Jan 2024 · Shift 1

    Identify the physical quantity that cannot be measured using spherometer :

    1. A.Radius of curvature of concave surface
    2. B.Specific rotation of liquids
    3. C.Thickness of thin plates
    4. D.Radius of curvature of convex surface
    Show answer

    Answer: B

21. Q412024 · 27 Jan 2024 · Shift 1

    The radius of third stationary orbit of electron for Bohr's atom is R. The radius of fourth stationary orbit will be:

    1. A.$\frac{4}{3}R$
    2. B.$\frac{16}{9}R$
    3. C.$\frac{3}{4}R$
    4. D.$\frac{9}{16}R$
    Show answer

    Answer: B

22. Q452024 · 27 Jan 2024 · Shift 1

    A body of mass $1000\text{ kg}$ is moving horizontally with a velocity $6\text{ m/s}$. If $200\text{ kg}$ extra mass is added, the final velocity (in $\text{m/s}$) is:

    1. A.$6$
    2. B.$2$
    3. C.$3$
    4. D.$5$
    Show answer

    Answer: D

23. Q512024 · 27 Jan 2024 · Shift 1· Numerical answer

    A particle starts from origin at $t=0$ with a velocity $5\hat{i}\text{ m/s}$ and moves in $x-y$ plane under action of a force which produces a constant acceleration of $(3\hat{i}+2\hat{j}){\text{m/s}}^2$. If the $x$-coordinate of the particle at that instant is $84\text{ m}$, then the speed of the particle at this time is $\sqrt{\alpha }\text{ m/s}$. The value of $\alpha$ is ________.

    Show answer

    Answer: 673

24. Q322024 · 27 Jan 2024 · Shift 2

    A ball suspended by a thread swings in a vertical plane so that its magnitude of acceleration in the extreme position and lowest position are equal. The angle $(\theta )$ of thread deflection in the extreme position will be :

    1. A.${\tan }^{-1}\left(\frac{1}{2}\right)$
    2. B.$2{\tan }^{-1}\left(\frac{1}{2}\right)$
    3. C.$2{\tan }^{-1}\left(\frac{1}{\sqrt{5}}\right)$
    4. D.${\tan }^{-1}(\sqrt{2})$
    Show answer

    Answer: B

25. Q382024 · 27 Jan 2024 · Shift 2

    The atomic mass of ${}_6{\text{C}}^{12}$ is $12.000000\text{ u}$ and that of ${}_6{\text{C}}^{13}$ is $13.003354\text{ u}$. The required energy to remove a neutron from ${}_6{\text{C}}^{13}$, if mass of neutron is $1.008665\text{ u}$, will be :

    1. A.$62.5\text{ MeV}$
    2. B.$6.25\text{ MeV}$
    3. C.$4.95\text{ MeV}$
    4. D.$49.5\text{ MeV}$
    Show answer

    Answer: C