Cylinder Falling from Unwinding String

[milanocookie]

Homework Statement

Iron cylinder with radius r has a string wound around it. As cylinder falls it unwinds string. Write an equation that relates the forces that act on the cylinder to its linear accceleration a, along with an equation that relates the torques that act on the cylinder to its angular acceleration a.

Relevant Equations

Moment of inertia of a solid cylinder is I= ½mr²

I need help with this homework question and I'm blanking out. Can anyone help me to answer this question correctly.

 

[kuruman]

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https://www.physicsforums.com/threads/homework-help-guidelines-for-students-and-helpers.686781/

 

[BvU]

Can anyone help me to answer this question correctly.

Break it up in steps!

A good first step is to make a drawing that shows relevant variables

A natural second step is to collect relevant equations connecting these variables

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