Work and kinetic energy of two blocks

AI Thread Summary
When two blocks of different masses slide on a frictionless surface and have the same kinetic energy, the lighter block (m2) will travel farther on a rough surface due to its higher initial speed. Although m2 has less momentum, it experiences a smaller frictional force, allowing it to maintain its velocity longer. The heavier block (m1) will decelerate more quickly because of its greater mass and the resulting frictional force. The conclusion is that m2, with its lesser mass and higher speed, will cover a greater distance before coming to a stop. This highlights the relationship between mass, speed, and friction in determining the distance traveled.
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Homework Statement


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?


Homework Equations



W = Fd..iono?!?

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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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
 
just so you know..answer came out to be m2..
go figure??
 
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.
 
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