Question

A box of bananas weighing 40.0 N rests on a horizontal surface. The coefficient of static friction between the box and the surface is 0.40 and the coefficient of kinetic friction is 0.20.
(a) If no horizontal force is applied to the box and the box is at rest, how large is the friction force exerted on it?
(b) What is the magnitude of the friction force if a monkey applies a horizontal force of 6.0N to the box and the box is initially at rest?

Answer 1

Answer:

(a) = 0 N

(b) = 2.4 N

Explanation:

given

box of banana weight = 40.0 N

coefficient of static friction  μ = 0.40

coefficient of kinetic friction = 0.20

a).  when no horizontal force is applied .

according to Newton 's third law of motion If there is no force applied to the box,so the frictional  force exerted is 0 N

b) magnitude of friction force

box and the box is initially at rest

    friction force =.Static friction coefficient × weight of the box

      friction force = 0.40 × 6

       friction force =  2.4 N