Question Detail
Question
Meter rule balances when pivoted at 50cm because
Correct Answer
Option A is the correct answer.
Detailed Explanation
A meter rule balances at its center (50 cm) because the center of mass is at the midpoint. When pivoted there, the weight of the rule acts through the pivot, producing no torque. The distances (and therefore the torques) on both sides are equal if the rule is uniform.
Hint
Balance occurs when the center of mass is above or below the pivot point.