Physics, asked by sangamithrarc, 3 days ago

4. For each of the following cases, indicate whether the work done on the second object in each example

will have a positive or a negative value.

a. The road exerts a friction force on a speeding car skidding to a stop.

b. A rope exerts a force on a bucket as the bucket t is raised up a well.

c. Air exerts a force on a parachute as the parachutist falls to Earth.

Answers

Answered by shkulsum3

A) The road exerts a friction force on a speeding car skidding to a stop.

The friction force acts in the opposite direction to the motion of the car, so the work done by the friction force on the car will be negative.

b. A rope exerts a force on a bucket as the bucket is raised up a well. The rope exerts a force in the upward direction, which is the same direction as the motion of the bucket. So the work done by the rope on the bucket will be positive.

c. Air exerts a force on a parachute as the parachutist falls to Earth. The air exerts a force on the parachute in the opposite direction to the motion of the parachutist, so the work done by the air on the parachute will be negative.