NEET Physics Energy Conservation of Energy and Momentum MCQs

Question. A light and a heavy body have equal momentum. Which one has greater K.E.?
(a) The lighter body
(b) The heavier body
(c) Both have equal K.E.
(d) Data given is incomplete

Answer: A

Question. Kinetic energy, with any reference, must be
(a) positive
(b) zero
(c) negative
(d) None of these

Answer: A

Question. Work done by a conservative force is positive if
(a) P.E. of the body decreases
(b) P.E. of the body increases
(c) K.E. of the body increases
(d) K.E. of the body decreases

Answer: A

Question. The ...X... energy V(x) of the spring is said to be zero when block and spring system is in the ...Y... position
(a) potential, equilibrium
(b) kinetic, equilibrium
(c) mechanical, equilibrium
(d) vibrational, left

Answer: A

Question. If stretch in a spring of force constant k is tripled then the ratio of elastic potential energy in the two cases will be
(a) 9 : 1
(b) 1 : 6
(c) 3 : 1
(d) 1 : 3

Answer: A

Question. If a shell fired from a cannon, explodes in mid air, then
(a) its total kinetic energy increases
(b) its total momentum increases
(c) its total momentum decreases
(d) None of these

Answer: A

Question. Total ....X.... energy of a system is conserved, if the forces, doing work on it, are .....Y..... . Here, X and Y refer to
(a) mechanical, conservative
(b) conservative, mechanical
(c) mechanical, non-conservative
(d) kinetic, conservative

Answer: A

Question. A bullet is fired and gets embedded in block kept on table. If table is frictionless, then
(a) momentum gets conserved
(b) potential energy gets conserved
(c) kinetic energy gets conserved
(d) None of these

Answer: A

Question. The speed of an object of mass m dropped from an inclined plane (frictionless), at the bottom of the plane, depends on
(a) height of the plane above the ground
(b) angle of inclination of the plane
(c) mass of the object
(d) All of these

Answer: A

Question. One man takes 1 min. to raise a box to a height of 1 metre and another man takes 1/2 min. to do so. The energy of the
(a) two is same
(b) second is more
(c) two is different
(d) first is more

Answer: A

Question. If the momentum of a body is increased by 50%, then the percentage increase in its kinetic energy is
(a) 125%
(b) 200%
(c) 100%
(d) 50%

Answer: A

Question. A ball dropped from a height of 2m reaches to a height of 1.5m before hitting the ground. Then the percentage of potential energy lost is
(a) 25
(b) 30
(c) 50
(d) 100

Answer: A

Question. A body of mass 0.5 kg travels in a straight line with velocity v = 5x3/2. The work done by the net force during the displacement from x = 0 to x = 2m is
(a) 50 J
(b) 75 J
(c) 100 J
(d) 25 J

Answer: A

Question. Four particles given, have same momentum. Which has maximum kinetic energy
(a) Electron
(b) Proton
(c) None of these
(d) Deutron

Answer: A

Question. The potential energy of a system increases if work is done
(a) upon the system by a conservative force
(b) upon the system by a non conservative force
(c) by the system against a non conservative force
(d) by the system against a conservative force

Answer: A

Question. If two particles are brought near one another, the potential energy of the system will
(a) increase
(b) remains the same
(c) decrease
(d) equal to the K.E

Answer: A

Question. A steel ball of mass 5g is thrown downward with velocity 10 m/s from height 19.5 m. It penetrates sand by 50 cm. The change in mechanical energy will be (g = 10 m/s2)
(a) 1.25 J
(b) 1.5 J
(c) 1.75 J
(d) 1J

Answer: A