Thread: Determine the distance of the center of gravity from the end X of the plank

Question:
A non-uniform plank of wood XY is 2.50m long and weighs 950N. Force-meters (spring balances) A and B are attached to the plank at a distance of 0.40m from each end, as illustrated in the Figure below

When the plank is horizontal, force-meter A records 570N
(i) Calculate the reading on force-meter B
(ii) Determine the distance of the center of gravity from the end X of the plank.

Attempt:
(i)


(ii) I don't know how to solve this question, need help!

Originally Posted by looi76

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(ii) I don't know how to solve this question, need help![/SIZE][/FONT]

I've modified your drawing a little bit.

Use momenti. The turning point of the plank is the point at forcemeter B:



Therefore the center of mass is 1.4 m from the endpoint Y that means it is 1.1 m from the endpoint X.