# Static Equilibrium of mass and wire

## Homework Statement

A 345 kg mass is supported on a wire attached to a 15 m long steel bar that is pivoted at a vertical wall and supported by a cable. The mass of the bar is 95 kg. (Take right and up to be positive.)

http://img522.imageshack.us/img522/8374/1265alt.gif" [Broken]

(a) With the cable attached to the bar 5.0 m from the lower end as shown, find the tension in the cable.
10003.6976 N (Done)

Find the force exerted by the wall on the steel bar.
5001.8488 N i + -4347.056 N j (Done)

(b) A somewhat longer cable replaces the old and is attached to the steel bar 5.0 m from its upper end, connecting to the same place on the wall as before and maintaining the same angle between the bar and the wall. Find the tension in the cable.
? N

Find the force exerted by the wall on the steel bar.
? N i + ? N j

## Homework Equations

Sum of Torques = 0
Sum of Fy = 0
Sum of Fx = 0

## The Attempt at a Solution

(b)
[(95kg)(9.81)(7.5m)(cos60) + (345kg)(9.81)(15m)(cos60)] / 10m
= 2887 N This is wrong

I haven't attepmted the second part of B because I need the tension to do so.

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unable to portrait the picture of problm..
can you please put up the figure..