# Unwinding Cylinder

#### jamaicanking

1. The problem statement, all variables and given/known data
Find the Linear momentum of an unwinding Cylinder with one end of a string attached to the ceiling. The mass of the cylinder is m and radius r. The cylinder is uniform and there is no slipping.

2. Relevant equations
Momentum, P = mv
moment of inertia , I = 1/2 MR^2

3. The attempt at a solution
distance from ceiling to point on cylinder , y = l(length of string unwound)

so is the momentum simply m*dl(t)/dt?

Last edited:
Related Introductory Physics Homework News on Phys.org

#### kuruman

Homework Helper
Gold Member
Yes. Draw a free body diagram, apply Newton's Second Law for rotational and linear motion, find the linear acceleration and use it to find l(t).

"Unwinding Cylinder"

### Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving