Unit 3: The Effect of Natural Forces on your Vehicle

Road surface changes due to: (a) ice, (b) rain, (c) snow, (d) oil and diesel fuel buildup, or (e) sand or dirt will reduce the traction of your tires. This does not affect the control of your vehicle.

False

The force of a moving object is called momentum. The momentum of an object is proportional to its weight and speed. The more momentum it has, the more force it has. So if there were two cars, both the same model, and one of the cars was traveling 30 mph faster than the other, which car has more force?

The faster car

If you are parking facing downhill, you should always turn your front wheels _______the curb or side of the road.

Towards

When should you always engage your parking brake?

When parking on an incline.

In order to keep a vehicle in a turn without allowing centrifugal force to pull the car out, what should you not do?

Accelerate while turning.

What is the best protection against injury if you have an accident?

Your seatbelt

What is the purpose of barrels filled with sand in front of an abutment (such as a support for a highway over pass)?

To reduce the force of impact on your vehicle by allowing your vehicle to travel farther than if it hit the abutment directly.

The force of a vehicle increases as its momentum increases.

True

Friction is_________ if your tires are over-inflated or are worn smooth. This makes it ______for you to stop you vehicle.

decreased, harder

Gravity __________ your kinetic energy when you are driving uphill and __________it when you are driving downhill.

decreases, increases