Question

A cart starting from rest rolls down a frictionless 1.0 m high hill. It travels a distance 2.0 m along the rough bottom surface until it comes to rest. What is the coefficient of kinetic friction along the bottom surface?

a. 4 m/s.
b. 0.5 m/s.
c. 25 m/s.
d. 7 m/s.
e. 6 m/s.

Answer 1

Option B is correct.

Step-by-step explanation:

Given data

Height of the hill = AB = 1 m

Distance traveled along the rough bottom surface = AC = 2 m

Now from the ΔABC

`\sin \theta = (AB)/(AC)`

`\sin \theta = (1)/(2)`

`\theta = 30` °

We know that the coefficient of kinetic friction is

`\mu = \tan \theta`

`\mu = \tan 30`

`\mu =` 0.5

This is the value of the coefficient of kinetic friction

Thus option B is correct.