Two balls, X and Y, move along a horizontal frictionless surface, as illustrated in Fig. 3.36.

Ball X has an initial velocity of 3.0 ms in a direction along line AB. Ball Y has a mass of 2.5 kg and an initial velocity of 9.6 ms-1 in a direction at an angle of 60° to line AB. The two balls collide at point B. The balls stick together and then travel along the horizontal surface in a direction at right angles to the line AB, as shown in Fig. 3.37.

a. By considering the components of momentum in the direction from A to B, show that ball X has a mass of 4.0 kg. [2]

b. Calculate the common speed V of the two balls after the collision. [2]

c. Determine the difference between the initial kinetic energy of ball X and the initial kinetic energy of ball Y. [2]

*AS Level Physics*
(Picture of both figures / diagrams below)

☆ Give the answer and method please, thank you! ☆
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