Kinetic Energy A body of mass (4m) is lying in x-y plane at rest. It suddenly explodes into three pieces. Two pieces, each of mass (m) move perpendicular to each other with equal speeds (v). The total kinetic energy generated due to explosion is Ruhul Amin Alig
Kinetic Energy Before a rubber ball bounces off from the floor, the ball is in contact with the floor for a fraction of second. Which of the following statements is correct? (a) Conservation of energy is not valid during this period (b) Conservation of energy is valid during this period (c) As ball is compressed, kinetic energy is converted to compressed potential energy (d) None of these Ruhul Amin Alig
Kinetic Energy A particle moves in a straight line with retardation proportional to its displacement. Its loss of kinetic energy for any displacement x is proportional to Ruhul Amin Alig
Kinetic Energy An electron and a proton are moving under the influence of mutual forces. In calculating the change in the kinetic energy of the system during motion, one ignores the magnetic force of one on another. This is because, (a) the two magnetic forces are equal and opposite, so they produce no net effect. (b) the magnetic forces do no work on each particle. (c) the magnetic forces do equal and opposite (but nonzero) work on each particle. (d) the magnetic forces are necessarily negligible. Ruhul Amin Alig
Kinetic Energy At time t = 0s particle starts moving along the x-axis. If its kinetic energy increases uniformly with time t, the net force acting on it must be proportional to Ruhul Amin Alig
Kinetic Energy Kinetic energy, with any reference, must be (a) zero (b) positive (c) negative (d) both (b) and (c) Ruhul Amin Alig
Kinetic Energy According to work-energy theorem, the work done by the net force on a particle is equal to the change in its (a) kinetic energy (b) potential energy (c) linear momentum (d) angular momentum Ruhul Amin Alig
Kinetic Energy In an explosion, a body breaks up into two pieces of unequal masses. In this (a) both parts will have numerically equal momentum (b) lighter part will have more momentum (c) heavier part will have more momentum (d) both parts will have equal kinetic energy Ruhul Amin Alig
Kinetic Energy A cricket ball is hit at an angle of 30° to the horizontal with a kinetic energy E. Its kinetic energy when it reaches the highest point is (a) E/2 (b) 0 (c) 2E/3 (d) 3E/4 Ruhul Amin Alig
Kinetic Energy A ball is thrown upwards and it returns to ground describing a parabolic path. Which of the following has the same value at the time of throw and the time of return? I. Kinetic energy of the ball II. Speed of the ball III. Vertical component of velocity (a) I and II (b) II and III (c) III only (d) I, II and III Ruhul Amin Alig
Kinetic Energy A truck and a car are moving with equal velocity. On applying the brakes both will stop after certain distance, then (a) truck will cover less distance before rest (b) car will coverless distance before rest (c) Both will cover equal distance (d) None of these Ruhul Amin Alig
Kinetic Energy Assertion: Formula for kinetic energy is K = 1 2 mu2 = ma Reason : Both the equation K = 1 2 mv2 and k = ma are dimensionally incorrect Ruhul Amin Alig
