Question

3. An object with a mass of 10 kg is moving along a horizontal surface. At a certain point it has 40 J of kinetic energy. If the coefficient of friction between the object and the surface is 0.40, how far will the object go beyond that point before coming to a stop? Use g = 10 m/s2

Answer 1

Answer: 100cm

Explanation:

The force of friction on a surface normal to gravity where µ is the coefficient of friction is

F = µmg

Where

F = the friction force

µ = coefficient of friction

m = mass of the object

g = acceleration due to gravity

Also, the Kinetic Energy of the object, E = Fs, where

E = Kinetic Energy

s = stopping distance. So that,

E = µmgs

40 J = 0.4 * 10 kg * 10 m/s² * s

40 J = 40 kgm/s² * s

s = 40 J / 40 kgm/s²

s = 1 m or 100 cm