Other Physics · JEE Main previous year questions

2004 15 questions

1. Q702004 · 24 Apr 2004 · Shift 1

   A ball is released from the top of a tower of height h meters. It takes T seconds to reach the ground. What is the position of the ball in $\frac{T}{3}$ seconds?

   1. A.$\frac{8h}{9}$ meters from the ground
   2. B.$\frac{7h}{9}$ meters from the ground
   3. C.$\frac{h}{9}$ meters from the ground
   4. D.$\frac{7h}{18}$ meters from the ground
   Show answer

   Answer: A

2. Q712004 · 24 Apr 2004 · Shift 1

   If $\vec{A}\times \vec{B}=\vec{B}\times \vec{A}$, then the angle between A and B is

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

   Answer: C

3. Q732004 · 24 Apr 2004 · Shift 1

   Which of the following statements is FALSE for a particle moving in a circle with a constant angular speed?

   1. A.The velocity vector is tangent to the circle.
   2. B.The acceleration vector is tangent to the circle.
   3. C.The acceleration vector points to the centre of the circle.
   4. D.The velocity and acceleration vectors are perpendicular to each other.
   Show answer

   Answer: B

4. Q742004 · 24 Apr 2004 · Shift 1

   An automobile travelling with speed of 60 km/h, can brake to stop within a distance of 20 m. If the car is going twice as fast, i.e 120 km/h, the stopping distance will be

   1. A.60 m
   2. B.40 m
   3. C.20 m
   4. D.80 m
   Show answer

   Answer: D

5. Q752004 · 24 Apr 2004 · Shift 1

   A ball is thrown from a point with a speed $v_0$ at an angle of projection θ. From the same point and at the same instant person starts running with a constant speed $\frac{v_0}{2}$ to catch the ball. Will the person be able to catch the ball? If yes, what should be the angle of projection θ?

   1. A.No
   2. B.Yes, $30^{\circ }$
   3. C.Yes, $60^{\circ }$
   4. D.Yes, $45^{\circ }$
   Show answer

   Answer: C

6. Q822004 · 24 Apr 2004 · Shift 1

   A particle is acted upon by a force of constant magnitude which is always perpendicular to the velocity of the particle, the motion of the particles takes place in a plane. It follows that

   1. A.its kinetic energy is constant
   2. B.is acceleration is constant
   3. C.its velocity is constant
   4. D.it moves in a straight line
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   Answer: A

7. Q832004 · 24 Apr 2004 · Shift 1

   A machine gun fires a bullet of mass $40\mathrm{g}$ with a velocity $1200\mathrm{m}{\mathrm{s}}^{-1}$. The man holding it can exert a maximum force of $144\mathrm{N}$ on the gun. How many bullets can he fire per second at the most?

   1. A.Two
   2. B.Four
   3. C.One
   4. D.Three
   Show answer

   Answer: D

8. Q942004 · 24 Apr 2004 · Shift 1

   If the temperature of the sun were to increase from $T$ to $2T$ and its radius from $R$ to $2R$, then the ratio of the radiant energy received on earth to what it was previously will be

   1. A.$32$
   2. B.$16$
   3. C.$4$
   4. D.$64$
   Show answer

   Answer: D

9. Q1112004 · 24 Apr 2004 · Shift 1

   Thermistors are usually made of

   1. A.metal oxides with high temperature coefficient of resistivity
   2. B.metals with high temperature coefficient of resistivity
   3. C.metals with low temperature coefficient of resistivity
   4. D.semiconducting materials having low temperature
   Show answer

   Answer: A

10. Q1122004 · 24 Apr 2004 · Shift 1

    Time taken by a $836\mathrm{W}$ heater to heat one litre of water from $10^{\circ }\mathrm{C}$ to $40^{\circ }\mathrm{C}$ is

    1. A.$150\mathrm{s}$
    2. B.$100\mathrm{s}$
    3. C.$50\mathrm{s}$
    4. D.$200\mathrm{s}$
    Show answer

    Answer: A

11. Q1132004 · 24 Apr 2004 · Shift 1

    The thermo $emf$ of a thermocouple varies with temperature $\theta$ of the hot junction as $E=a\theta +b{\theta }^2$ in volts where the ratio $a/b$ is $700^{\circ }\mathrm{C}$. If the cold junction is kept at $0^{\circ }\mathrm{C}$, then the neutral temperature is

    1. A.$1400^{\circ }\mathrm{C}$
    2. B.$350^{\circ }\mathrm{C}$
    3. C.$700^{\circ }\mathrm{C}$
    4. D.No neutral temperature is possible for this termocouple.
    Show answer

    Answer: D

12. Q1172004 · 24 Apr 2004 · Shift 1

    Curie temperature is the temperature above which

    1. A.a ferromagnetic material becomes paramagnetic
    2. B.a paramagnetic material becomes diamagnetic
    3. C.a ferromagnetic material becomes diamagnetic
    4. D.a paramagnetic material becomes ferromagnetic
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    Answer: A

13. Q1212004 · 24 Apr 2004 · Shift 1

    Two long conductors, separated by a distance $d$ carry current $I_1$ and $I_2$ in the same direction. They exert a force $F$ on each other. Now the current in one of them is increased to two times and its direction is reversed. The distance is also increased to $3d$. The new value of the force between them is

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

    Answer: A

14. Q1232004 · 24 Apr 2004 · Shift 1

    The materials suitable for making electromagnets should have

    1. A.high retentivity and low coercivity
    2. B.low retentivity and low coercivity
    3. C.high retentivity and high coercivity
    4. D.low retentivity and high coercivity
    Show answer

    Answer: B

15. Q1402004 · 24 Apr 2004 · Shift 1

    The manifestation of band structure in solids is due to

    1. A.Bohr's correspondence principle
    2. B.Pauli's exclusion principle
    3. C.Heisenberg's uncertainty principle
    4. D.Boltzmann's law
    Show answer

    Answer: B