# What is the net torque on the pulley about the axle

#### aligass2004

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

What is the net torque on the pulley about the axle if T1 = 18N and T2 = 34N?
http://i241.photobucket.com/albums/ff4/alg5045/p13-11.gif

2. Relevant equations

3. The attempt at a solution

Torque is really confusing me. I have no ideas as to how to start this problem.

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#### TVP45

You're gonna have to show some work, but to "push" you along... could you get started if there were only 1 force?

#### aligass2004

I know that torque = r(Ft), but I don't know if that's the right equation to use.

#### TVP45

I'm guessing that Ft is the force that is perpendicular to the radius. Is that what you mean? If so, that is the right equation.

To give a longer answer than you might want,
Torque = force x radius x sine of the angle between the force and the radius.
In many cases, the angle is 90 degrees (it certainly is in your picture) and sin(90) = 1, so torque = force x radius in those cases.

So, now can you calculate the two torques, ONE AT A TIME, including whether it goes clockwise (CW) or counterclockwise (CCW)?

#### aligass2004

I figured it out before looking at your last post. Thanks though!

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