(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The wall crane in Fig. 3 supports a load of 800 N. Determine the horizontal and vertical

components of reaction at the pins A and D. Also, what is the force in the cable at the winch

W?

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2. Relevant equations

Newton's Laws of Motion, Moment, Equilibrium of Forces

3. The attempt at a solution

First I draw a free body diagram at B. The vertical forces involved are the y component of the tension in rod BD and the y component of the tension of cable WB.

Since the tension of a massless cable is the same throughout the string, the tension of the cable is 400N. Substituting the value of T_{WB}to the above equation, I get T_{BD}=490N.

However, a problem occurs when I attempt to find T_{BD}by taking the moment at A. The solution for T_{BD}turns out to be 2752N.

What cause the difference in the answer?

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# Static, Moment

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