Answer: A. Tennis ball hit into a net
Step-by-step explanation:
Momentum = m.v (where m = mass of object and v = velocity of object)
However, the velocity of the ball is in a direction +x
The mass of the ball is definitely comstant. However, the ball's velocity is subject to change - both in magnitude and direction.
When the ball is hit at one side of the court, it assumes a velocity u.
Its momentum at u = m.u-->
(--> representing the direction)
Immediately it crashes into the net,both the magnitude and direction of its velocity experience a sharp change as it is hurled in a direction opposite its former direction.
Obviously, the correct answer is option A