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Ok im completely stuck on this question, i have some idea on how to do it and know it is to do with moments but i cant figure out where to take the moments.
Calculate the value of YBar for the Isection shown below, where YBar is the vertical height of the centroid of the section above its base.
YBar x Area of shape = XA * AA + XB * AB + XC * AC
YBar x Area of shape = XA * AA + XB * AB + XC * AC
so
YBar x 12,000 = XA * 3600 + XB * 3600 + XC * 4800
YBar = (XA * 3600 + XB * 3600 + XC * 4800) / 12,000
I have gone through my notes and several text books but i cant work out where to take the moments to get the XA, XB and XC values. Its probably obvious but if someone can give me a nudge in the right direction it would be appreciated.
Homework Statement
Calculate the value of YBar for the Isection shown below, where YBar is the vertical height of the centroid of the section above its base.
Homework Equations
YBar x Area of shape = XA * AA + XB * AB + XC * AC
The Attempt at a Solution
YBar x Area of shape = XA * AA + XB * AB + XC * AC
so
YBar x 12,000 = XA * 3600 + XB * 3600 + XC * 4800
YBar = (XA * 3600 + XB * 3600 + XC * 4800) / 12,000
I have gone through my notes and several text books but i cant work out where to take the moments to get the XA, XB and XC values. Its probably obvious but if someone can give me a nudge in the right direction it would be appreciated.
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