Why is the center of mass assumed to be on the vertical in an arc?

[abdo799]

Homework Statement

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Homework Equations

The Attempt at a Solution

i have the solution , but in it , he assumes the center of mass is on the vertical and thus the distance of the vertical from the center is rsin(1/4∏)/(1/4∏) where r is the radius , so why did he take this assumption?

 

[Simon Bridge]

he assumes the center of mass is on the vertical ... so why did he take this assumption?

The wire is freely suspended from point A.
If the com was not vertically below point A, then what would happen?

 

[abdo799]

Thanks, i got it

 

[Simon Bridge]

Well done :)