A 2.5 kg block is thrown along a floor at 7.0 m/s.
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
A block is thrown along a floor at . The coefficient of kinetic friction is . Taking , find how far it slides and how much heat is produced.
Need a reminder? The key ideaShow
With friction, total energy is still conserved: , and the heat is the work against friction, the path length.
The worked solution
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Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Given. , , .
Plan. The heat equals the kinetic energy; divide by the friction for the distance.
Step 1. Heat. .
Step 2. Friction. .
Step 3. Distance. .
Answer: It slides and produces of heat.
Check. , with the mass cancelling. Same.
Watch out. The distance does not depend on the mass, but the heat does.
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