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looi76
Jun11-08, 06:45 AM
1. The problem statement, all variables and given/known data
A long uniform beam is pivoted at one end. A force of 300N is applied to hold the beam horizontally.
http://img182.imageshack.us/img182/4219/11062008vt2.png
What is the weight of the beam?

2. Relevant equations
Don't know which question to use... need help!


3. The attempt at a solution

armis
Jun11-08, 07:08 AM
The principle of the lever tells us that
{F_1}\sdot{d_1} = {F_2}\sdot{d_2}

http://www.edinformatics.com/math_science/simple_machines/LeverPrinciple.png

I think that's all you need to solve it

Doc Al
Jun11-08, 08:55 AM
Ask yourself:
(1) What forces act on the beam? Where do they act?
(2) What torque do they exert about the pivot point?
(3) Since the beam is in equilibrium, what must be the net torque?