# Homework Help: Atwood machines

1. Nov 29, 2006

### Tonyt88

There is an Atwood's machine. The masses of blocks A and B are m_A and m_B, respectively, the moment of inertia of the wheel about its axis is I, and the radius of the semicircle in which the string moves is R.

Known: m_A > m_B

a)Find the magnitude of the linear acceleration of the block A.
b)Find the magnitude of the linear acceleration of the block B.
c)What is the magnitude of the angular acceleration of the wheel C?
d)Find the magnitude of the tension in the left side of the cord if there is no slipping between the cord and the surface of the wheel.
e)Find the magnitude of the tension in the right side of the cord if there is no slipping between the cord and the surface of the wheel.

Okay, so I have:

m_A*a = m_A*g - T_A

m_B*a = T_B -m_B*g

I(alpha) = T_A*R - T_B*R

a = R(alpha)

Am I missing something, or...

2. Nov 30, 2006

### Staff: Mentor

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