# Homework Help: Compare forces exerted between the Tennis Racquets

1. Oct 10, 2014

### DanielC90

1. The problem statement, all variables and given/known data
During a tennis volley, a ball that arrives at a player at
40 m/s is struck by the racquet and returned at 40 m/s. The other player, realizing that the ball is out of bounds, catches it in her hand.
Assuming the time interval of contact is the same in both cases, compare the force exerted by the first player's racquet on the ball with the force exerted by the second player's hand on the ball.

2. Relevant equations
None given. The book did not provide me with one I could use.

3. The attempt at a solution
I have submitted 0 as my answer because I felt that with both of them going the same speed, there would be 0 difference in force, but I got this problem incorrect (5 more attempts remaining at the time of this message). Mass is not given either, so how would one find the difference of force between these two using only velocity?

2. Oct 11, 2014

### haruspex

What is the change in velocity in each case?

3. Oct 11, 2014

### DanielC90

judging from the given variables, there's no change.

4. Oct 11, 2014

### dotmatrix

-40m/s

5. Oct 11, 2014

### NTW

The player with the racket holds and returns the ball. The other player does not return the ball...
A big difference...

Last edited: Oct 11, 2014
6. Oct 11, 2014

### haruspex

The ball approaches the racket at 40 m/s. After being hit by the racket, it is moving at 40 m/s in the opposite direction. Velocity is a vector. What is the magnitude of the change in velocity? (It is not zero.)

7. Oct 11, 2014

### DanielC90

Ahhh ok... I was worn out yesterday so I couldn't figure that out.

Last edited: Oct 11, 2014