Net Torque

1. Jun 26, 2008

00PS

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

A block of mass m1 = 1.80 kg and a block of mass m2 = 6.05 kg are connected by a massless string over a pulley in the shape of a solid disk having radius R = 0.250 m and mass M = 10.0 kg. These blocks are allowed to move on a fixed block-wedge of angle θ = 30.0° as in Figure P10.37. The coefficient of kinetic friction is 0.360 for both blocks

Determine the acceleration of the two blocks, and the tension on the right side of the pulley.

2. Relevant equations

tNET=Iw<---omega
I(disk)=(1/2)mr^2

3. The attempt at a solution

I used the equation above for net torque and found that a(tangential)=(r*tNET)/I. I know the tensions of the blocks times the radius gives me the torque but wouldn't one of them be negative? I am also having trouble finding the net forces on the blocks.

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2. Jun 26, 2008

Staff: Mentor

OK.
One tension force exerts a clockwise torque, the other a counterclockwise torque.
Analyze the forces on each block and apply Newton's 2nd law. That will give you two more equations.

3. Jun 26, 2008

00PS

thanks Doc, I figured out the problem...I forgot to compensate for the second mass on an incline hence, trig. ughhh...