1 last problem in physics?

Question

A 1270 N uniform beam is attached to a vertical wall at one end and is supported by a cable at the other end. A W = 1860 N crate hangs from the far end of the beam

(a) Calculate the magnitude of the tension in the wire. Newtons

(b) Calculate the magnitude of the horizontal and vertical components of the force that the wall exerts on the left end of the beam

Fx = N
Fy = N

http://img107.imageshack.us/img107/9378/p966altcu2.gif

Answer 1

Summing torques at the pivot on the wall
with clockwise as positive
sin(60)*1270*L/2+sin(60)*1860*L=
T*sin(80)*L

where L is the length of the beam and T is the tension in the cable

T=sin(60)*(1270/2+1860)/sin(80)
T=2194 N

Summing the forces in x and y
By=3130-2194*cos(40)
=1449 N
Bx=2194*sin(40)
=1410
Check by summing torques at the center of the beam
By*sin(60)*L/2+1860*sin(60)*L/2-
Bx*sin(30)*L/2-2194*sin(80)=0

Checks

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