An 80-kg man is one fourth of the way up a 10-m ladder that is resting against a smooth,frictionless wall.If the ladder has a mass of 30 kg and it makes an angle of 60° with the ground,find the force of friction of the ground on the foot of the ladder. A) 7.8 × 10² N B) 2.0 × 10² N C) 50 N D) 1.7 × 10² N

Question

Quizplus · Accepted Answer

The force of friction at the base of the ladder is equal to the horizontal component of the force exerted by the wall. By calculating the torques about the base and using equilibrium conditions, the force of friction is found to be 2.0 × 10² N.

An 80-Kg Man Is One Fourth of the Way Up