A uniform ladder long and of mass rests in equilibrium with its upper end against a…
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A uniform ladder 4.0m long and of mass 20kg rests in equilibrium with its upper end against a smooth vertical wall and its lower end on a rough horizontal ground. The ladder makes an angle of 60∘ with the ground. Take the foot of the ladder as the axis for moments and g=9.8ms−2.
(a) State the position of the centre of gravity of the ladder with respect to its length.
(b) Calculate the perpendicular distance of the weight of the ladder from the foot.
(c) Hence find the magnitude and sense (clockwise or counter-clockwise) of the moment of the ladder’s weight about the foot.