Suppose the ski patrol lowers a rescue sled and victim, having a total mass of 90.0 kg, down a 60.0º slope at constant speed, as shown in Figure 7.37. The coefficient of friction between the sled and the snow is 0.100. (a) How much work is done by friction as the sled moves 30.0 m along the hill? (b) How much work is done by the rope on the sled in this distance? (c) What is the work done by the gravitational force on the sled? (d) What is the total work done?

Step 1 of 6</p>

The sled and victim, having a total mass of ,coming downward at slope at a constant speed is shown in the figure below.

Step 2 of 6</p>

a) We need to find out the work done by friction as the sled moves along the hill.

The work done by friction is nothing but the sum of frictional force and the distance moved by the sled is given by,

..............(1)

We know that the coefficient of friction is

So

Put this value in equation (1)

From figure

Then

distance

Coefficient of friction

Acceleration due to gravity

angle

Then

work done by friction as the sled moves along the hill is

Step 3 of 6</p>

b) We need to find out how much work is done by the rope on the sled.

Let T is the Tension of the rope.

from figure

Implies

We found out the value of

Put this value in the above equation