In a physical balance working on the principle of moments, when 5 mg weight is placed on the left pan, the beam becomes horizontal. Both the empty pans of the balance are of equal mass. Which of the following statements is correct ?

Options

A. Left arm is longer than the right arm
B. Both the arms are of sae length
C. Left arm is shorter than the right arm
D. Every object that is weighed using this balance appears lighter than its actual weight.

Answer

C

Explanation

According to principle of moments when a system is stable or balance, the anti-clockwise moment is equal to clockwise moment.
i.e., load `xx` load arm = effort `xx` effort arm
When 5 mg weight is placed, load arm shifts to left side, hence left arm becomes shorter than right arm.