Hello, I have a weight that is connected by a string and the string is wrapped a

Question

Hello, I have a weight that is connected by a string and the string is wrapped around a circular disk.

So when the weight is falling due to gravity, the disk is rotating and letting the string get longer. Naturally, the acceleration is no longer 9.81 m/s^2 due to the string wrapped around the disk. By the way, friction is reduced with air going into the apparatus.

My question is, how does the shape's inertia affect the acceleration of the weight falling down due to gravity?

I also have the combination of the disk and a rectangle placed on top of it. For this last part, I can only think of adding the two moments of inertia, but I still don't see how that affects the acceleration of the falling weight.

Explanation / Answer

Torque acting on the pulley = moment of inertia of the pulley * alpha

T = I*alpha

and torque = Tension*R = FR = mgR-maR

mgR-maR = I*a/R

a = mgR^2/(I + maR^2)

Related Questions

Navigate

• Browse (All)
• Browse H
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.