# A block ‘ of mass hits horizontally the rear side of a spring (ideal) attached to a block of mass resting on a smooth horizontal surface. After hitting, ‘ gets attached to the spring Some statements are given at any moment of time: I. If velocity of is greater than then kinetic energy of the system will be decreasing ii. If velocity of is greater than then kinetic energy of the system will be increasing iii. If velocity of is greater than then momentum of the system will be decreasing iv. If velocity of is greater than then momentum of the system will be increasing Now select correct alternative: a) only iv b) only i c) ii.and iv d) i and iii

## Question ID - 100502 :- A block ‘ of mass hits horizontally the rear side of a spring (ideal) attached to a block of mass resting on a smooth horizontal surface. After hitting, ‘ gets attached to the spring Some statements are given at any moment of time: I. If velocity of is greater than then kinetic energy of the system will be decreasing ii. If velocity of is greater than then kinetic energy of the system will be increasing iii. If velocity of is greater than then momentum of the system will be decreasing iv. If velocity of is greater than then momentum of the system will be increasing Now select correct alternative: a) only iv b) only i c) ii.and iv d) i and iii

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 (b) Statement (i) is correct because in this case, spring would be compressing. So PE in the spring will be increasing. It means KE of the system will be decreasing as the total mechanical energy of the system is constant Further, momentum of the system will always be conserved. It will neither be increasing nor be decreasing

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On a smooth carom board,a coin moving in negative -direction with a speed of 3m/s is being hit at the point (4,6) by a striker moving along negative -axis. The line joining the centres of the coin and the striker just before the collision is parallel to -axis. After collision the coin goes into the hole located at the origin. Masses of the striker and the coin are equal. Considering the collision to be elastic,the initial and final speeds of the striker in m/s will be a) (1,0) b) (2,0) c) (3,0) d) None of these 