If a mass of 76 kg acts downward 0.38 m from the axis of rotation on one end of a board and another force of 129 N also acts downward, what is the moment arm of the second force to balance this system

y = 2.196 m

Explanation:

Mass, m = 76 kg

distance from axis of rotation, x = 0.38 m

Second Force, F = 129 N

moment arm of the second force, y = ?

Now, equating moments for the equilibrium

So,

m g × x = F x y

76 x 0.38 x 9.81 = 129 x y

y = 2.196 m

Hence, the length of the moment arm is equal to 2.196 m.