Question

Which effect will kinetic friction have on the car?

a) Keeps the race car from rolling while it is parked
b) Slows the car down once the tires lock and begin to slide
c) Tends to slow the vehicle down and is affected by the car's shape and size
d) Increases the speed of the car.

Answer 1

Kinetic friction acts to slow down a vehicle, such as a race car, by opposing its motion. It is distinct from static friction which prevents slipping during rolling motion without slipping. Friction also converts the vehicle's kinetic energy into heat, mostly observed in the brake system.

Step-by-step explanation:

Kinetic friction, when it pertains to a vehicle such as a race car, tends to slow the vehicle down. This friction occurs between the car's tires and the road surface when the tires are in motion. If a car accelerates too quickly causing the tires to spin without the car moving forward, this indicates the presence of kinetic friction. Then, as the vehicle slows down or comes to a stop, the kinetic energy is converted into heat, often observed in the car's brake pads and rotors. Moreover, the shape and size of the vehicle can affect how friction influences its movement, as larger vehicles or those with less aerodynamic shapes may experience greater frictional forces.

During rolling motion without slipping, such as when the car is moving forward steadily, the bottom of the tires deforms slightly due to static friction and is temporarily at rest with respect to the ground. This static friction is necessary to prevent the tires from slipping and is distinct from kinetic friction, which acts on a vehicle when it is already in motion and opposes the motion, thereby slowing it down.