OK I have 1 more question for today...(adsbygoogle = window.adsbygoogle || []).push({});

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

A 0.45kg volleyball travels witha horizontal velocity of 3.2m/s over the net. You jump up an hit the ball back witha horizontal velocity 7 m/s. If the contact time is 0.047s, what is the average force on the ball?

2. Relevant equations

Here are all the equations that were in our notes for this section.

p (momentum) There was triangle P and triange t in my notes, so I wrote "change in"

p=mv

f=ma

f*"change in"t="change in"p

f*"change in"t=mv_{f}-mv_{i}

"change in" P=mv_{f}-mv_{i}

3. The attempt at a solution

Again, I wasnt really sure what equation to use...

[(.45kg)(-3.8m/s)-(.45kg)(3.2m/s)]/(.047s)

I got -67.0, but it wasn't right...

Please help...=]

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# Homework Help: Momentum and impulse of a volleyball

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