Work done shortening string of rotating object

1. The problem statement, all variables and given/known data



10kg is attached to the end of a string, which is thread through a vertical tube. The string and the tube always make a 90 degree angle. The distance from the tube to the mass is R and the velocity at which it rotates is V. How much work is done to shorten the distance from the tube to the mass to x?



__distance X________10kg

[l] string

[l]

[l] t

[l] u

[l] b

[l] e

[l]

.l

.l string











2. Relevant equations



work = torque * theta = r*F*sin(theta)







3. The attempt at a solution



string radius being shortened from X to x, so the displacement is (X-x)

does the velocity change?

1. The problem statement, all variables and given/known data







2. Relevant equations







3. The attempt at a solution

1. The problem statement, all variables and given/known data







2. Relevant equations







3. The attempt at a solution

1. The problem statement, all variables and given/known data







2. Relevant equations







3. The attempt at a solution

1. The problem statement, all variables and given/known data







2. Relevant equations







3. The attempt at a solution

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