Q3.11Multiple correct
A ball is bouncing elastically with a speed 1 m/s between walls of a railway compartment of size 10 m in a direction perpendicular to walls. The train is moving at a constant velocity of 10 m/s parallel to the direction of motion of the ball. As seen from the ground,
- (a)the direction of motion of the ball changes every 10 seconds.
- (b)speed of ball changes every 10 seconds.
- (c)average speed of ball over any 20 second interval is fixed.
- (d)the acceleration of ball is the same as from the train.