Other Physics · JEE Main previous year questions

2024 52 questions

1. Q442024 · 9 Apr 2024 · Shift 1

   A heavy iron bar, of weight $W$ is having its one end on the ground and the other on the shoulder of a person. The bar makes an angle $\theta$ with the horizontal. The weight experienced by the person is :

   1. A.$W\sin \theta$
   2. B.$W$
   3. C.$\frac{W}{2}$
   4. D.$W\cos \theta$
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   Answer: C

2. Q462024 · 9 Apr 2024 · Shift 1

   The energy equivalent of $1\text{ g}$ of substance is :

   1. A.$5.6\times 10^{26}\text{ MeV}$
   2. B.$5.6\times 10^{12}\text{ MeV}$
   3. C.$5.6\text{ eV}$
   4. D.$11.2\times 10^{24}\text{ MeV}$
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   Answer: A

3. Q482024 · 9 Apr 2024 · Shift 1

   An astronaut takes a ball of mass $m$ from earth to space. He throws the ball into a circular orbit about earth at an altitude of $318.5\text{ km}$. From earth's surface to the orbit, the change in total mechanical energy of the ball is $x\frac{\mathrm{G}{\mathrm{M}}_{\mathrm{e}}\mathrm{m}}{21{\mathrm{R}}_e}$. The value of $x$ is (take ${\mathrm{R}}_e=6370\text{ km}$) :

   1. A.12
   2. B.11
   3. C.9
   4. D.10
   Show answer

   Answer: B

4. Q542024 · 9 Apr 2024 · Shift 1· Numerical answer

   If $\vec{a}$ and $\vec{b}$ make an angle ${\cos }^{-1}\left(\frac{5}{9}\right)$ with each other, then $|\vec{a}+\vec{b}|=\sqrt{2}|\vec{a}-\vec{b}|$ for $|\vec{a}|=n|\vec{b}|$. The integer value of $n$ is ______.

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   Answer: 3

5. Q572024 · 9 Apr 2024 · Shift 1· Numerical answer

   A star has 100% helium composition. It starts to convert three ${}^4\mathrm{He}$ into one ${}^{12}\mathrm{C}$ via triple alpha process as ${}^4\mathrm{He}+{}^4\mathrm{He}+{}^4\mathrm{He}\to {}^{12}\mathrm{C}+\mathrm{Q}$. The mass of the star is $2.0\times 10^{32}\text{ kg}$ and it generates energy at the rate of $5.808\times 10^{30}\text{ W}$. The rate of converting these ${}^4\mathrm{He}$ to ${}^{12}\mathrm{C}$ is $\mathrm{n}\times 10^{42}{\text{ s}}^{-1}$, where $\mathrm{n}$ is ______. [ Take, mass of ${}^4\mathrm{He}=4.0026\text{u}$, mass of ${}^{12}\mathrm{C}=12\text{u}$]

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   Answer: 5

6. Q402024 · 9 Apr 2024 · Shift 2
   
   1. A.a solar cell
   2. B.a transistor which can be used as an amplifier
   3. C.a diode which can be used as a rectifier
   4. D.a zener diode which can be used as a voltage regulator
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   Answer: D

7. Q512024 · 9 Apr 2024 · Shift 2· Numerical answer

   The resultant of two vectors $\vec{A}$ and $\vec{B}$ is perpendicular to $\vec{A}$ and its magnitude is half that of $\vec{B}$. The angle between vectors $\vec{A}$ and $\vec{B}$ is ____${}^{\circ }$.

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   Answer: 150

8. Q312024 · 8 Apr 2024 · Shift 1

   A stationary particle breaks into two parts of masses $m_A$ and $m_B$ which move with velocities $v_A$ and $v_B$ respectively. The ratio of their kinetic energies $(K_B:K_A)$ is :

   1. A.$v_B:v_A$
   2. B.$1:1$
   3. C.$m_B{v}_B:m_A{v}_A$
   4. D.$m_B:m_A$
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   Answer: A

9. Q352024 · 8 Apr 2024 · Shift 1

   In an expression $a\times 10^b$ :

   1. A.$a$ is order of magnitude for $b\le 5$
   2. B.$b$ is order of magnitude for $a\le 5$
   3. C.$b$ is order of magnitude for $a\ge 5$
   4. D.$b$ is order of magnitude for $5<a\le 10$
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   Answer: B

10. Q362024 · 8 Apr 2024 · Shift 1

    A clock has $75\text{ cm},60\text{ cm}$ long second hand and minute hand respectively. In 30 minutes duration the tip of second hand will travel $x$ distance more than the tip of minute hand. The value of $x$ in meter is nearly (Take $\pi =3.14$) :

    1. A.$118.9$
    2. B.$140.5$
    3. C.$139.4$
    4. D.$220.0$
    Show answer

    Answer: C

11. Q382024 · 8 Apr 2024 · Shift 1

    A player caught a cricket ball of mass $150\text{ g}$ moving at a speed of $20\text{ m/s}$. If the catching process is completed in $0.1\text{ s}$, the magnitude of force exerted by the ball on the hand of the player is:

    1. A.$150\text{ N}$
    2. B.$3\text{ N}$
    3. C.$30\text{ N}$
    4. D.$300\text{ N}$
    Show answer

    Answer: C

12. Q392024 · 8 Apr 2024 · Shift 1

    Three bodies A, B and C have equal kinetic energies and their masses are $400\text{ g},1.2\text{ kg}$ and $1.6\text{ kg}$ respectively. The ratio of their linear momenta is :

    1. A.$1:\sqrt{3}:2$
    2. B.$\sqrt{3}:\sqrt{2}:1$
    3. C.$1:\sqrt{3}:\sqrt{2}$
    4. D.$\sqrt{2}:\sqrt{3}:1$
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    Answer: A

13. Q532024 · 8 Apr 2024 · Shift 1· Numerical answer
    
    Show answer

    Answer: 3

14. Q322024 · 6 Apr 2024 · Shift 2

    A body projected vertically upwards with a certain speed from the top of a tower reaches the ground in $t_1$. If it is projected vertically downwards from the same point with the same speed, it reaches the ground in $t_2$. Time required to reach the ground, if it is dropped from the top of the tower, is :

    1. A.$\sqrt{t_1+t_2}$
    2. B.$\sqrt{t_1{t}_2}$
    3. C.$\sqrt{\frac{t_1}{t_2}}$
    4. D.$\sqrt{t_1-t_2}$
    Show answer

    Answer: B

15. Q342024 · 6 Apr 2024 · Shift 2

    A body of weight $200\mathrm{N}$ is suspended from a tree branch through a chain of mass $10\mathrm{kg}$. The branch pulls the chain by a force equal to (if $g=10m/{\mathrm{s}}^2$) :

    1. A.$300\mathrm{N}$
    2. B.$100\mathrm{N}$
    3. C.$150\mathrm{N}$
    4. D.$200\mathrm{N}$
    Show answer

    Answer: A

16. Q352024 · 6 Apr 2024 · Shift 2

    The number of electrons flowing per second in the filament of a $110\mathrm{W}$ bulb operating at $220\mathrm{V}$ is : (Given $\mathrm{e}=1.6\times 10^{-19}\mathrm{C}$)

    1. A.$1.25\times 10^{19}$
    2. B.$31.25\times 10^{17}$
    3. C.$6.25\times 10^{18}$
    4. D.$6.25\times 10^{17}$
    Show answer

    Answer: B

17. Q442024 · 6 Apr 2024 · Shift 2

    The longest wavelength associated with Paschen series is : (Given ${\mathrm{R}}_{\mathrm{H}}=1.097\times 10^7\mathrm{SI}\mathrm{unit}$)

    1. A.$2.973\times 10^{-6}\mathrm{m}$
    2. B.$1.876\times 10^{-6}\mathrm{m}$
    3. C.$1.094\times 10^{-6}\mathrm{m}$
    4. D.$3.646\times 10^{-6}\mathrm{m}$
    Show answer

    Answer: B

18. Q482024 · 6 Apr 2024 · Shift 2

    Assuming the earth to be a sphere of uniform mass density, a body weighed $300\mathrm{N}$ on the surface of earth. How much it would weigh at $\mathrm{R}/4$ depth under surface of earth ?

    1. A.$75\mathrm{N}$
    2. B.$375\mathrm{N}$
    3. C.$300\mathrm{N}$
    4. D.$225\mathrm{N}$
    Show answer

    Answer: D

19. Q372024 · 5 Apr 2024 · Shift 2

    A man carrying a monkey on his shoulder does cycling smoothly on a circular track of radius $9\mathrm{m}$ and completes 120 revolutions in 3 minutes. The magnitude of centripetal acceleration of monkey is (in $m/{\mathrm{s}}^2$) :

    1. A.$4{\pi }^2{\mathrm{ms}}^{-2}$
    2. B.$16{\pi }^2{\mathrm{ms}}^{-2}$
    3. C.$57600{\pi }^2{\mathrm{ms}}^{-2}$
    4. D.Zero
    Show answer

    Answer: B

20. Q362024 · 4 Apr 2024 · Shift 1

    If a rubber ball falls from a height $h$ and rebounds upto the height of $h/2$. The percentage loss of total energy of the initial system as well as velocity of ball before it strikes the ground, respectively, are :

    1. A.$50\%,\sqrt{2\mathrm{gh}}$
    2. B.$50\%,\sqrt{\mathrm{gh}}$
    3. C.$50\%,\sqrt{\frac{\mathrm{gh}}{2}}$
    4. D.$40\%,\sqrt{2\mathrm{gh}}$
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    Answer: A

21. Q392024 · 4 Apr 2024 · Shift 1

    A body travels $102.5\mathrm{m}$ in ${\mathrm{n}}^{\mathrm{th}}$ second and $115.0\mathrm{m}$ in $(\mathrm{n}+2{)}^{\mathrm{th}}$ second. The acceleration is :

    1. A.$6.25m/{\mathrm{s}}^2$
    2. B.$5m/{\mathrm{s}}^2$
    3. C.$12.5m/{\mathrm{s}}^2$
    4. D.$9m/{\mathrm{s}}^2$
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    Answer: A

22. Q412024 · 4 Apr 2024 · Shift 1

    The co-ordinates of a particle moving in $x$-$y$ plane are given by : $x=2+4t$, $y=3t+8t^2$. The motion of the particle is :

    1. A.uniform motion along a straight line.
    2. B.non-uniformly accelerated.
    3. C.uniformly accelerated having motion along a straight line.
    4. D.uniformly accelerated having motion along a parabolic path.
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    Answer: D

23. Q482024 · 4 Apr 2024 · Shift 1
    
    1. A.
    2. B.
    3. C.
    4. D.
    Show answer

    Answer: D

24. Q502024 · 4 Apr 2024 · Shift 1

    On Celsius scale the temperature of body increases by $40^{\circ }\mathrm{C}$. The increase in temperature on Fahrenheit scale is :

    1. A.$75^{\circ }\mathrm{F}$
    2. B.$70^{\circ }\mathrm{F}$
    3. C.$72^{\circ }\mathrm{F}$
    4. D.$68^{\circ }\mathrm{F}$
    Show answer

    Answer: C

25. Q572024 · 4 Apr 2024 · Shift 1· Numerical answer

    Two forces ${\overline{\mathrm{F}}}_1$ and ${\overline{\mathrm{F}}}_2$ are acting on a body. One force has magnitude thrice that of the other force and the resultant of the two forces is equal to the force of larger magnitude. The angle between ${\vec{F}}_1$ and ${\vec{F}}_2$ is ${\cos }^{-1}\left(\frac{1}{n}\right)$. The value of $|n|$ is ____.

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    Answer: 6