Question

A figure shows a uniform metre rule which is pivoted at the 20cm mark and balanced horizontally by an object of weight 3.15N placed at the 10cm mark.
Calculate the weight of the metre rule.

Answer 1

assume the cg of the meter stick is at the 50cm mark.

Summing moments from the 0 cm mark.
-3.15*.1+(W*.2)=0
W=3.15*.5 N

Answer 2

Not satisfying