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Pulling an Unwinding Spool vs. Standard Block
This problem is done on a frictionless surface
There is a block pulled by a string with tension T.
Next to it, there is a spool with a string wrapped around it and may unwind. It is pulled with the same tension as System A. The spool is standing on its base, so it slides, and doesn't roll.
The question is whether the block or spool will cross the finish line first, which force does more work, and whether the total kinetic energy (trans. + rot.) are equal.
conceptual
They should cross the line at the same time because it shouldn't matter where the force is applied, the object will still accelerate at the same speed. However, the spool should have more total KE because it is spinning and moving when it crosses the finish line, which also means more work is done on it. What I'm confused about is where the extra work comes from. Does the force on the spool do more work because the string is also unwinding, so the force acts over a greater distance than the force acting on the block?
Homework Statement
This problem is done on a frictionless surface
There is a block pulled by a string with tension T.
Next to it, there is a spool with a string wrapped around it and may unwind. It is pulled with the same tension as System A. The spool is standing on its base, so it slides, and doesn't roll.
The question is whether the block or spool will cross the finish line first, which force does more work, and whether the total kinetic energy (trans. + rot.) are equal.
Homework Equations
conceptual
The Attempt at a Solution
They should cross the line at the same time because it shouldn't matter where the force is applied, the object will still accelerate at the same speed. However, the spool should have more total KE because it is spinning and moving when it crosses the finish line, which also means more work is done on it. What I'm confused about is where the extra work comes from. Does the force on the spool do more work because the string is also unwinding, so the force acts over a greater distance than the force acting on the block?
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