Question

A 30.6 kilogram object is pulled by a horizontal force of 243 newtons causing it to accelerate at 5 meters per second squared. What is the force of friction acting on the
object? Calculate the coefficient of friction of the two surfaces.

Answer 1

Answer:

Ffriction = 90 N

coefficient = 0.3

Explanation:

First, note that the sum of all the forces in the x directions equals the mass multiplied by the acceleration in the x direction.

assuming the direction of the pulling force is positive,

243 N - Ffriction = m * a

m= 30.6 kg

a= 5 m/s/s

Ffriction= 243 - m*a

Ffriction= 243 - (30.6)(5)

Ffriction=90 N

The force of friction is equal to the coefficient of friction multiplied by the normal force on the object. Because the pulling force is completely horizontal, the normal force of the object is equal to its weight, which is m * g, or (30.6 kg)(9.8 m/s/s) = 299.88 N

Ffriction = coefficient * Fnormal

90 = coefficient * 299.88

coefficient = 0.3