(adsbygoogle = window.adsbygoogle || []).push({}); In the figure below, the pulley is a solid disk of mass M and radius R, with rotational inertia (MR^{2})/2. Two blocks, one of mass m_{1}, and one of mass m_{2}, hang from either side of the pulley by a light cord. Initially, the system is at rest, with Block 1 on the floor and Block 2 held at heighthabove the floor. Block 2 is then released and allowed to fall.

a. What is the speed of Block 2 just before it strikes the ground?

b. What is the angular speed of the pulley at this moment?

c. What's the angular displacement of the pulley?

d. How long does it take for Block 2 to fall to the floor?

(MR^{2})/2 = I

mgh=GPE

(mv^{2})/2 =KE_{trans}

Iw(omega)^{2}=KE_{rot}

I can't figure out how to do it, but the answers are

a. v = sqrt((2gh(m_{2}-m_{1}))/(m_{1}+m_{2}+(M/2)))

b. w(omega) = (1/R) * sqrt((2gh(m_{2}-m_{1}))/(m_{1}+m_{2}+(M/2)))

c. ???????

d. t =h* sqrt((2m_{1}+2m_{2}+M)/(gh(m_{2}-m_{1})))

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# Homework Help: Atwood Machine, Rotational Inertia, and Energy

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