# Tension in cable

A 225 kg uniform square sign, 2.00 m on a side, is hung from a 3.00 m rod of negligible mass. A cable is attached to the end of the rod and to a point on the wall 4.00 m above the point where the rod is fixed to the wall. What is the tension in the cable?
I know I need to use:
sum of Fx
sum of Fy
sum of Torque

What I'm wondering is how should I do this when I don't know any angles whatsoever? Any help on this would be useful, just knowing this should get me through the problem.

## Answers and Replies

PhanthomJay
Science Advisor
Homework Helper
Gold Member
bearhug said:
A 225 kg uniform square sign, 2.00 m on a side, is hung from a 3.00 m rod of negligible mass. A cable is attached to the end of the rod and to a point on the wall 4.00 m above the point where the rod is fixed to the wall. What is the tension in the cable?
I know I need to use:
sum of Fx
sum of Fy
sum of Torque

What I'm wondering is how should I do this when I don't know any angles whatsoever? Any help on this would be useful, just knowing this should get me through the problem.
The rod is 3 m and the cable is attached 4 m up from the wall. Now if the sign was just a point load at the end of the rod, the angle would be arctan 4/3, correct?