- #1

giacomh

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## Homework Statement

http://imgur.com/vXkg0

## Homework Equations

Fw=γAH

Ycp=bh

^{3}/(12)(h/2)b + (h/2)

## The Attempt at a Solution

I found the angle of the gate from the horizontal to be 53.1 degrees. Using this, I found y to be 2.5m and H (vertical distance to centroid) to be 6 m (2.5sin(53.1)+4).

I then found Fw=9810*6*(4*5)=1177200N, and Ycp=(4*5

^{3})/(12*20*2.5) +2.5=3.33m.

By taking the moment at the ground, I found Fw*(5-3.33)-5P=0, so P= 393kN. My book says the answer should be 523 kN. Help please.