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## Homework Statement

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?

[URL=http://imageshack.us][PLAIN]http://img182.imageshack.us/img182/992/tutorialse0.jpg[/URL] http://g.imageshack.us/g.php?h=182&i=tutorialse0.jpg [Broken][/PLAIN]

## Homework Equations

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

## 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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