Question

uniform mementum mas is 90g is pivoted at 40cm mark if the metra rula ia in equilibrium with an mark unknown mass m place at the 10cm mark and mass of 73g place at 70cm .ditermine the value of m when mass of an object is always at it center of gravity​

Answer 1

Answer:

Unknown mass, $m = 14 \textrm{ g}$

Explanation:

From the figure below,

OE is a meter scale with markings in centimeter.

A is the position of unknown mass m, B is the position of 90 g mass, C is the fulcrum, D is the position of mass 73 g.

Length AC = 40 cm, BC = 10 cm, CD = 20 cm

For equilibrium of the meter scale,

Sum of anti-clockwise moments = Sum of clockwise moments

$F_{A}\times AC+F_{B}\times BC=F_{D}\times CD\\m\times 40+90\times10=73\times20\\40m+900=1460\\40m=1460-900\\40m=560\\m=\frac{560}{40}=14\textrm{ g}$

Therefore,unknown mass is 14 g.