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## Homework Statement

A uniform diving board, of length 5.0 m and mass 53 kg, is supported at two points; one support is located 3.4 m from the end of the board and the second is at 4.6 m from the end (see the figure below). What are the forces acting on the board due to the two supports when a diver of mass 64 kg stands at the end of the board over the water? Assume that these forces are vertical. [Hint: In this problem, consider using two different torque equations about different rotation axes. This may help you determine the directions of the two forces.]

http://www.webassign.net/grr/chapter-08/fig-019.gif

## Homework Equations

formula derived from image and question

## The Attempt at a Solution

N

_{1}is the left support and N

_{2}is the left support.

(sigma)(Torque)= N

_{1}-N

_{2}-W

_{e}-W

_{p}then since the right support = o since it is the axis of rotation I solve accordingly for the left support force :

1.2N

_{1}=2.1W

_{e}+4.6W

_{p}

N

_{1}=(2.1(53)(9.8)+4.6(64)(9.8))/1.2

N

_{1}= 3313.21N or 3.313kN

I have tried taking the left support to be the axis of rotation and solved accordingly. I always end up with the answer that is correct for the other support(I have the answers from webassign but I never understood it the first time through and I am reviewing for a test) The answer ends up being 2.17 kN for the left support downwards and 3.31kN for the right support upwards. What am I doing wrong and why do I get the answer for the other support? Is it just coincidence? After I find the correct force for the one I know I can just take the summation of the forces and subtract to get the force acting on the other support.