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

Multiple Choice

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