Problem 28P

A 1100-kg car coasts on a horizontal road with a speed of 19 m/s. After crossing an unpaved, sandy stretch of road 32 m long, its speed decreases to 12 m/s. (a) Was the net work done on the car positive, negative, or zero? Explain. (b) Find the magnitude of the average net force on the car in the sandy section.

Solution 28P:

Step 1 of 3:-

Here we need to find whether the work done is positive, negative or zero.

The mass of the car is: .

The initial speed was: .

After crossing the sandy road, the final speed became,

.