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mburt
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Homework Statement
The diagram below shows a 2.0 × 103 kg truck on a 20.0 m long uniform bridge that has a mass of 8.0 × 103 kg. If the truck is 6.0 m from support A, what is the magnitude of the upward force at support B?
[PLAIN]http://img534.imageshack.us/img534/6554/torquev.png
Homework Equations
T = rFsin(x)
The Attempt at a Solution
[PLAIN]http://img17.imageshack.us/img17/5487/torqueattempt.png
Tclockwise = Tcounterclockwise
Ttruck + Tbridge = TB
(6.0m)(2000 kg)(9.80 m/s^2) + (10.0m)(8 000kg)(9.80m/s^2) = (20.0m)F
90160 Nm / 20.0m = F
F = 4.5x104 N
However the answer given is 4.6x103 N.
Any thoughts?
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