When a 58 g tennis ball is served, it accelerates from rest to a constant speed of 35 m/s. The impact with the racket gives the ball a constant acceleration over a distance of 48 cm. What is the magnitude of the net force acting on the ball?

Question

turingtest · Answer

the most neglected kinematic equation is$$v_f^2=v_i^2+2ad$$in this case the initial velocity is zero, so this becomes$$v_f^2=2ad$$which you can use to find acceleration. From there you can find the force with$$F=ma$$

anonymous · Answer

But of course i might add, (might be beyond your level but good to know), it comes with the assumption that,  whent the ball accelerates, it is with constant acceleration and upon reaching the distance of 48cm, the acceleration just cuts off.  because in a real situation, the accleration would slowly decrease until the tennis ball hits its constant speed (discounting air resistance)

anonymous · Answer

But aren't real time situatioins ignored for this part of mechanics? Now that we are in the real life situation, this must be an impulse.

anonymous · Answer

no no im just saying that the question did not state that the ball upon hitting the distance of 48cm , hit the constant speed of 35m/s. Because if you read too much into the question, you would think that the ball have constant acceleration until the 48cm mark, and still carry on increasing in speed, but with decreasing accleration. if it comes to this, this question cannot be solved already.

anonymous · Answer

Oh, yeah i got your point! But if you read it with some insight you get it :D