Question

A sled of mass 15 kg slides across the ground with a friction force of 80.85 N. What is k between the sled and the ground?

Answer 1

The expression for the frictional force between the sled and the ground is:
$F=k m g$
where $k$ is the coefficient of friction, m is the mass of the object and $g=9.81 m/s^2$ is the gravitational acceleration.

The friction force in our problem is F=80.85 N. The mass of the object is m=15 kg. Re-arranging the formula, we can find the value of k:
$k= \frac{F}{mg}= \frac{80.85 N}{(15 kg)(9.81 m/s^2)}=0.55$

Answer 2

0.55 is correct - APEX