## Kinetic Energy Question

1. The problem statement, all variables and given/known data
A 7.0 kg bowling ball moves at 2.35 m/s. How fast must a 2.40 g Ping-Pong ball move so that the two balls have the same kinetic energy?

m1= 7.0kg
v1= 2.35m/s
m2= .0024kg
v2=?

2. Relevant equations

I know that:
KE= 1/2mv^2

3. The attempt at a solution
I set my equation like so:
KE1=KE2

and I reduced it to this:
m1v1=m2v2

I plugged in the values and solved for v2:
(7.0kg)(2.35m/s)=v2 (.0024kg)
v2= 6854.17

I put this answer in and it tells me...
wrong check mark

What am I doing wrong? Please point me in the right direction.
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 Quote by islanderman7 I know that: KE= 1/2mv^2
Good.

 3. The attempt at a solution I set my equation like so: KE1=KE2
Good.

 and I reduced it to this: m1v1=m2v2
You made an error here. The kinetic energy equation doesn't reduce to this.

(Don't leave off squaring the speeds.)
 Thank you Doc Al. The correct answer was 127m/s