# Work and kinetic energy of two blocks

#### msattar07

1. The problem statement, all variables and given/known data
Two blocks of mass m1 and m2 (m1 > m2) slide on a frictionless floor and have the same kinetic energy when they hit a long rough stretch (coeff. of kinetic friction > 0), which slows them down to a stop. Which one goes farther?

2. Relevant equations

W = Fd..iono?!?

3. The attempt at a solution

i think the answer is mass 2 because it has a smaller mass which will allow it to travel a farther distance.

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#### phyguy321

i think its a tie because they have the same KE and using the energy balance they would cancel out and go just as far

#### msattar07

just so you know..

answer came out to be m2..
go figure?!?!

#### Math Jeans

Yes. I believe it is m2.

Because it has a lesser mass, in order for the kinetic energies to be the same, it must be traveling faster than the heavier mass.

Although it has less momentum, it also has less of a frictional force opposing it, and because it has a faster initial speed, it should go further than the heavier block.

"Work and kinetic energy of two blocks"

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