(b) Two balls X and Y, of equal diameter but different masses 0.24kg and 0.12kg respectively, slide towards each other on a frictionless horizontal surface, as shown in [Fig. 2.1]. Both balls have initial speed 2.3ms⁻¹ before they collide with each other. [Fig. 2.2] shows the variation with time t of the force Fy exerted on ball Y by ball X during the collision.

1. (a)Define momentum.[1]
2. (b)(i)Calculate the kinetic energy of ball X before the collision.[3]
3. (b)(ii)The area enclosed by the lines and the time axis in [Fig. 2.2] represents the change in momentum of ball Y during the collision. Determine the magnitude of the change in momentum of ball Y.[2]
4. (b)(iii)Calculate the magnitude of the velocity of ball Y after the collision.[2]
5. (c)On [Fig. 2.3], sketch the variation with time t of the force Fx exerted on ball X by ball Y during the collision in (b).[3]

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