# Pulleys/Static equilibrium

1. May 12, 2009

### xdevinx

1. The problem statement, all variables and given/known data

Find the mass m of the counterweight needed to balance the 1600 kg truck on the incline. Assume all pulleys are frictionless and massless.

Picture attached

2. Relevant equations

Conditions for static equilibrium so that angular acceleration=0:
$$\sum$$Torque=0

3. The attempt at a solution

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2. May 12, 2009

### tiny-tim

Welcome to PF!

Hi xdevinx! Welcome to PF!

I can't see the diagram yet, but if this is a standard weight-pulley-weight problem, then rotational dynamics and torque and irrelevant …

just call the tension T, and use good ol' Newtons second law twice (once on each weight).