The coefficient of kinetic friction between a 50 kg crate and the warehouse floor is 80 % of the corresponding coefficient of static friction. The crate falls off a forklift that is moving at 4 m/s and then slides along the warehouse floor for a distance of 2.5 m before coming to rest.

What is the coefficient of static friction between the crate and the floor?

In this answer, the value of the acceleration of gravity is taken as 9.8 m/s2

Coefficient of static friction = 0.409

Explanation:

Kinetic friction is responsible for bringing the crate to rest.

Initial velocity, u = 4 m/s

Final velocity, v = 0 m/s

Distance, s = 2.5 m

We use the equation of motion to find the acceleration, a.

The negative sign denotes the crate was decelerating.

Kinetic friction = mass of crate × acceleration

Coefficient of kinetic friction = kinetic friction/weight of crate

is 80% of , coefficient of static friction