A seesaw in a playground is a uniform plank of length 3.0 m pivoted exactly at its centre.
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A seesaw in a playground is a uniform plank of length 3.0 m pivoted exactly at its centre.
(i) A child of mass 40 kg sits at the left end. At what distance from the pivot should another child of mass 50 kg sit on the right side so that the seesaw remains horizontal?
(ii) If the heavier child instead sits 1.2 m from the pivot on the right side, calculate the magnitude and sense (clockwise or counter-clockwise) of the net moment about the pivot.