A uniform ladder of length and mass rests against a smooth vertical wall
PHYSICS · Subjective · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A uniform ladder of length 4.0m and mass 20kg rests against a smooth vertical wall, making an angle of 60∘ with the horizontal rough ground.
(i) Calculate the magnitude of the torque due to the weight of the ladder about the point where the ladder touches the ground.
(ii) The ladder is now shifted so that it makes an angle θ with the ground while the point of contact at the foot remains the same. If the required torque about the foot is to be 120N m, determine the new angle θ (in degrees) that the ladder must make with the ground.