### Book Store

Currently only available for.
CBSE

# JEE Physics 2010 Exam Questions

#### Multiple Choice Questions

1.

STATEMENT – 1
Two particles moving in the same direction do not lose all their energy in a completely inelastic collision.
STATEMENT – 2
Principle of conservation of momentum holds true for all kinds of collisions.

• The statement I is True, Statement II is False.

• The statement I is True, Statement II is True; Statement II is a correct explanation for Statement I.

• The statement I is True, Statement II is True; Statement II is not the correct explanation for Statement I.

• Statement I is False, Statement II is

B.

The statement I is True, Statement II is True; Statement II is a correct explanation for Statement I.

264 Views

2.

A particle is moving with velocity, where K is a constant. The general equation for its path is

• y = x2 + constant

• y2 =  x + constant

• xy = constant

• y2 = x2 + constant

D.

y2 = x2 + constant

The velocity of the particle,

164 Views

3.

A small particle of mass m is projected at an angle θ with the x–axis with an initial velocity v0 in the x–y plane as shown in the figure. At a time t<vosin/g, the angular momentum of the particle is

C.

The angular momentum  of the projectile is given by,
L = m (r x v)

821 Views

4.

A ball is made of a material of density ρ where ρoil < ρ < ρwater with ρoil and ρwater representing the densities of oil and water, respectively. The oil and water are immiscible. If the above ball is in equilibrium in a mixture of this oil and water, which of the following pictures represents its equilibrium position?

C.

ρoil < ρ < ρwater
Oil is the least dense of them, so it should settle at the top with water at the base. Now, the ball is denser than oil but less denser than water. So, it will sink through oil but will not sink in water. So, it will stay at the oil -water interface.

443 Views

5.

Two fixed frictionless inclined planes making an angle 30° and 60° with the vertical are shown in the figure. Two blocks A and B are placed on the two planes. What is the relative vertical acceleration of A with respect to B?

• 4.9 ms-2 in horizontal direction

• 9.8 ms-2 in vertical direction

• zero

• 4.9 ms-2 in vertical direction

D.

4.9 ms-2 in vertical direction

For the motion of block along inclined plane
mg sin θ =ma
a = g sin θ
where a is along the inclined plane.
The vertical component of acceleration is g sin2θ
Therefore, the relative vertical acceleration of  A with respect to B is
g (sin260 - sin230) = g/2 = 4.9 ms-2 (in vertical direction)

453 Views

6.

For a particle in uniform circular motion, the acceleration an at point P (R, θ) on the circle of radius R is (Here θ is measured from the x–axis)

C.

675 Views

7.

The figure shows the position –time (x – t) graph of one–dimensional motion of a body of mass 0.4 kg. The magnitude of each impulse is

• 0.4 (Ns)

• 0.8 Ns

• 1.6 Ns

• 0.2 Ns

B.

0.8 Ns

From the graph it is a straight line, so uniform motion. Because of impulse direction of velocity changes as can be seen from the slope of the graph.
(∴ impulse (l) = f x t
⇒ I  = mat

Initial velocity, v1 = 2/2 = 1 ms-1
Final velocity v2 = 2/2 = - 1 ms-1
pi  = mv1 = 0.4 N-s
pf  = mv2 = -0.4 N-s
J = pf-pi = -0.4-0.4
= - 0.8 N-s
|J| = 0.8 N-s

438 Views

8.

A diatomic ideal gas is used in a Carnot engine as the working substance. If during the adiabatic expansion part of the cycle the volume of the gas increases from V to 32 V,the efficiency of the engine is

• 0.5

• 0.75

• 0.99

• 0.25

B.

0.75

282 Views

9.

The respective number of significant figures for the numbers 23.023, 0.0003 and 2.1 × 10–3 are

• 5,1,2

• 5,1,5

• 5,5,2

• 4,4,2

A.

5,1,2

228 Views

10.

A point p moves in counter -clockwise direction on a circular path as shown in the figure. The movement of P is such that it sweeps out the length s = t3 + 5, where s is metre and t is in second. The radius of the path is 20 m. The acceleration of P when t =2 s is nearly

• 13 ms-2

• 12 ms-2

• 7.2 ms-2

• 14 ms-2

D.

14 ms-2

Given that, s  =t3 +5
therefore speed v, = ds/st = 3t2
and rate of change of speed, at = dv/dt = 6t
∴ Tangential acceleration at t =2s
at = 6 x 2  = 12 ms-1
and at t = 2s, v = 3 (2)2 = 12 ms-1
∴ Centripetal acceleration, ac = v2/R = 144/20 ms-2
∴ Net acceleration  =

383 Views

Do a good deed today
Refer a friend to Zigya