# Average force between baseball and bat

1. Nov 14, 2014

### Rachelbot12

1. The problem statement, all variables and given/known data

A 0.145- kg baseball with an initial speed of 20 m/s rebounds with a speed of 36 m/s after being struck with a bat. If the duration of contact between ball and bat was 2.4 ms, what was the magnitude of the average force between ball and bat?

2. Relevant equations
Δ velocity=Vf-Vi
F= mass* Δ velocity/(Δ time)

3. The attempt at a solution

Δ velocity = -36-20 = -56 m/s

mass* Δ velocity/(Δ time) = 56 m/s * 0.145 kg / .0024s
3383.333 N

2. Nov 14, 2014

### BvU

Hello Rachel, and welcome to PF :)

Seven digits precision is a bit much. Your calculation is just fine. Was that what you wanted to know ?
(In fact PF isn't really meant for stamp-approving homework -- I hope I don't get in trouble over this one...)

3. Nov 14, 2014

### Rachelbot12

The problem is that it's an online hw and the website is saying it's incorrect. Thank you though!

4. Nov 14, 2014

### Rachelbot12

Actually, I decided to try it without any decimal points and it turned out to be right. Weird. Thanks again :)