Q.1.
A block of mass 0.5kg is moving with a speed of 2.0m/s on smooth surface. It strikes another mass of 1.0kg and then they move together as a single body. The energy loss during collision is [AIEEE 2008]
-
100%
a) 0.16 J
-
0%
b) 1.0J
-
0%
c)0.67J
-
0%
d)0.34J
Q.2.
A body of mass 2kg is thrown up vertically with a kinetic energy 490J. If the gravitational acceleration due to gravity is 9.8 m/s2, the height at which the kinetic energy of the body becomes half of the original value is [ EAMCET 1986]
-
0%
a) 50 m
-
0%
b) 25 m
-
0%
c)12.5 m
-
100%
d)10 m
Q.3.
A 238U nucleus decays by emitting an alpha particle of speed v m/s. The recoil speed of the residual nucleus is ( m/s) [ CBSE 1995]
-
0%
a) -4v / 234
-
0%
b) v/4
-
100%
c) -4v/234
-
0%
d) 4v/238
Q.4.
You lift a heavy book from the floor of the room an put it in the book self having a height 2m. In this process you take 5sec. The work done by you will depend upon [ MPPET 1993]
-
0%
a)mass of the book and time taken
-
50%
b) weight of the book and the height of the book shelf
-
0%
c)height of the book shelf and the time taken
-
50%
d)mass of the book, height of the book shelf and the time taken
Q.5.
A particle moves under the effect of force F=cx, from x=0 to x=x1 the work done in the process is
-
0%
a) (cx12) /2
-
100%
b) cx12
-
0%
c)cx13
-
0%
d)zero
Explanation
Q.6.
Which of the following statement is true?
-
0%
a) momentum is conserved in elastic collisions but not in inelastic collisions
-
100%
b) total kinetic energy is conserved in elastic collisions but momentum is not conserved in elastic collisions
-
0%
c)total kinetic energy is not conserved but momentum is conserved in inelastic collisions
-
0%
d)kinetic energy and momentum are conserved in all types of collisions.
Q.7.
The principle of conservation of momentum can be strictly applied during a collision between two particles provided the time of impact is
-
50%
a) extremely small
-
0%
b) moderately small
-
50%
c) extremely large
-
0%
d) depends on a particular case
Q.8.
Work is done on the body when
-
0%
a)force acts on it
-
0%
b) it moves through a certain distance
-
0%
c)it experiences an increase in energy through a mechanical influence
-
100%
d)none of the above
Q.9.
Which one of the following statements does not hold good when two balls of mass m1 and m2 undergo elastic collision?
-
0%
a) when m1 < m2 and m2 are at rest, there will be maximum transfer of momentum
-
0%
b) when m1 > m2 and m2 are at rest, after collision the ball of m2 moves with four times the velocity of m1
-
50%
c)When m1 and m2 and m2 are at rest, there will be maximum transfer of K.E.
-
50%
d)when collision in oblique and m2 at rest with m1=m2, after collision the ball moves in same direction
Explanation
Q.10.
A block of weight W is pulled a distance l along a horizontal table. The work done by the weight is
-
0%
a) Wl
-
0%
b) 0
-
0%
c)Wgl
-
100%
d)Wl/g
Q.11.
A particle of mass m moving with a velocity v makes a head-on elastic collision with another particle of mass m initially at rest. The velocity of the first particle after collision will be [ MPPMT 1997]
-
0%
a) v
-
0%
b) - v
-
100%
c)-2v
-
0%
d)zero
Explanation
Q.12.
A car of mass 'm' is driven with acceleration 'a' along a straight road against a constant external resistance 'R'. When the velocity is 'v', the power of the engine is : [ MPPMT 1998]
-
0%
a) Rv
-
0%
b) mav
-
0%
c) (R+ma)v
-
100%
d) (R-ma)v
Q.13.
A uniform chain of mass M and length L lies on a frictionless table with length l0 hanging over the edge. The chain begins to slide down. Then the speed with which the end slides away from the edge is given by :
-
100%
a)
-
0%
b)
-
0%
c)
-
0%
d)
Explanation
Q.14.
A car is moving along a straight horizontal road with a speed v0 If the coefficient of friction between the tyres and the road is µ, the shortest distance in which the car can be stopped is .. [ MPPMT 1985]
-
0%
a)
-
0%
b)
-
100%
c)
-
0%
d)
Q.15.
A spring of force constant 10 N per meter has an initial stretch 0.20 m. In changing the stretch to 0.25m, the increase in potential energy is about
-
0%
a) 0.1 joule
-
0%
b) 0.2 joule
-
100%
c)0.3 joule
-
0%
d)0.5 joule
Q.16.
A particle moves in the x-y plane under the action of a force F such that the value of its linear momentum P at any time t is Px=2cost , Py=2sint the angle θ between F and P at any given time t will be [ MNR 1991]
-
0%
a) 90°
-
0%
b) 0°
-
100%
c) 180°
-
0%
d) 30°
Explanation
Q.17.
An engine pumps a liquid of density 'd' constantly through a pipe of area of cros section A. If the speed with which the liquid passes through a pipe is 'v', then the rate at which the kinetic energy is being imparted to the liquid is
-
0%
a)Adv3 / 2
-
0%
b) Ad v /2
-
100%
c)Adv2 / 2
-
0%
d)Adv2
Q.18.
A spring is compressed between two toy car of masses m and M. When the toy-cars are released, the spring exerts on each toy-car equal and opposite force for the same time t. If the coefficient of friction 'µ' between the ground and the toy-car are equal, then the displacement of the two toy-cars:
-
100%
a)
-
0%
b)
-
0%
c)
-
0%
d)
Explanation
Q.19.
If V, P and E denote the velocity, momentum and kinetic energy of the particle then
-
0%
a) P=dE/dV
-
0%
b) P=dE/dt
-
0%
c)P=dV/dt
-
100%
d)P=dE/dV × dE/dt
Q.20.
A weight hangs freely from the end of a spring. A boy then slowly pushes the weight upwards until the spring becomes slack. The gain in gravitational potential energy of the weight during this process is equal to
-
0%
a) the loss of stored energy by the spring minus the work done by the tension in the spring
-
0%
b) the work done on the weight by the boy plus the stored energy lost by the spring
-
100%
c) the work done on the weight by the body minus the work done by the tension in the spring plus the stored energy lost by the spring
-
0%
d) the work done on the weight by the boy minus the work done by the tension in the spring
Q.21.
A bullet is fired freely. If the rifle recoils freely, then
-
0%
a) the kinetic energy of the rifle is less than that of the bullet
-
0%
b) the kinetic energy of the rifle is greater than that of the bullet
-
0%
c) the kinetic energy of the rifle is equal to that of bullet
-
100%
d) the kinetic energy of rifle is zero
Q.22.
A man pushes a wall but fails to displace it, it does : [ CPMT 1992]
-
0%
a) negative work
-
0%
b) positive work
-
0%
c)no work at all
-
100%
d)maximum positive work
Q.23.
A lighter and a heavy body has equal kinetic energy which has greater momentum [ CPMT 1985]
-
0%
a)the heavy body
-
0%
b) the lighter body
-
100%
c)both have equal momentum
-
0%
d)none
Explanation
Q.24.
A bullet is fired freely. If the rifle recoils freely, then
-
0%
a) the kinetic energy of the rifle is less than that of the bullet
-
0%
b) the kinetic energy of the rifle is greater than that of the bullet
-
100%
c) the kinetic energy of the rifle is equal to that of bullet
-
0%
d) the kinetic energy of rifle is zero
Q.25.
A particle is moving with a momentum of 10 kgm/s. A force of 0.2N acts on it in the direction of motion of the particle for 10 s. If the mass of the particle is 5kg, the increase in kinetic energy is [ MPPET 1999]
-
0%
a)4.4J
-
0%
b) 3.8J
-
0%
c)3.2J
-
100%
d)2.8J
Q.26.
A block of mass M slides along the sides of a flat bottomed bowl. The sides of the bowl are frictionless and the base has a coefficient of friction 0.If the block is released from the top of the side which is 1.5m height, where will the block come to rest. Given, the length of the base is 15m
-
0%
a) 1 m from P
-
0%
b) mid point of flat part PQ
-
100%
c)2m from P
-
0%
d)at Q
Q.27.
If a man increases his speed by 2m/s, his Kinetic energy is doubled. The original speed of the man is
-
0%
a) (2 + √2) m/s
-
0%
b) (2+2√2) m/s
-
0%
c)4 m/s
-
100%
d)( 1 +2√2) m/s
Q.28.
Work done in raising a box depends on
-
0%
a) How fast it is raised
-
0%
b) The height by which it is raised
-
0%
c)The strength of the man
-
100%
d)None of the above
Q.29.
The potential energy between to atoms in a molecule is given by where a and b are positive constants and x is the distance between the atoms. The atoms is in stable equilibrium when:
-
0%
a)
-
100%
b)
-
0%
c) zero
-
0%
d)
Q.30.
A smooth sphere of M moving with velocity u directly collides elastically with another sphere of mass m at rest. After collision, their final velocity are V and v, respectively. The value of v is : [ MPPMT 1995]
-
0%
a)
-
100%
b)
-
0%
c)
-
0%
d)
