A rope pulls a trolley 14 m along a level path.
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
A rope pulls a trolley along a level path. The tension is , and the rope makes with the path. How much work does the rope do?
Need a reminder? The key ideaShow
The work done by a steady force is , in joules. It is positive when the force helps the motion, zero when the force is at right angles to it, and negative when it opposes it. From parts: .
The worked solution
Have you tried it?
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. .
Step 1. .
Answer: About .
Check. It is a little less than , the work of a level rope. A gentle slant costs only a little.
Watch out. would give the work of the lifting part, which is zero here, since the trolley does not rise.
Discussion (0)
Log in to join the discussion.
Loading…