1. lesson 9.1 GRAVITY AND ENERGY OF MOTION
Drive Right chapter 9
Friday, July 26, 2019
lesson 9.1
GRAVITY AND ENERGY OF MOTION
The motion of your vehicle is subject to the natural laws of motion.
These laws include inertia, momentum, energy of motion, and gravity.
In emergency situations, these natural laws can work for or against you.
The copyright holder has not granted permission to display this photograph in a downloadable format. You may view the photograph in the Drive Right Presentation for this lesson on your Keys to Teaching Success disc.
Version 2

2. Describe how inertia affects your vehicle while going straight and while driving through a curve.
OBJECTIVE

3. Inertia, Momentum, and Energy of Motion
The law of inertia:
Objects that are at rest tend to stay at rest and objects that are moving tend to keep moving.
Inertia is keeping these cars at rest. For the cars to move, they must be acted upon by forces produced by the engine.

4. Once the car is moving, inertia causes the car and everything in it to continue moving in a straight line at a constant speed until acted upon by another force.
Here are three examples of how inertia affects passengers in cars.

5. You can feel inertia when a car brakes rapidly
You can feel inertia when a car brakes rapidly. As the car slows down, inertia causes your body to continue to move forward.
How does your body feel when the car brakes rapidly?
What would happen if you were not wearing a safety belt?

6. How does inertia affect your body when a car accelerates rapidly?
What causes that effect?

7. How does inertia affect you when a car drives around a sharp curve?
What causes that effect?

8. Define momentum.
OBJECTIVE

9. Momentum is the tendency of an object to stay in motion, or the inertia of an object in motion.
The amount of momentum depends upon the object’s weight and speed.
Does the truck or car have the most momentum?

10. Identify the factors that affect energy of motion.
OBJECTIVE

11. A moving object also has energy of motion, or kinetic energy, that changes in proportion to the weight of the vehicle.
Does the truck or car have the most energy of motion?

12. A vehicle’s energy of motion is proportional to the square of its speed.
Double your speed and your vehicle will:
have four times as much energy of motion
need four times as much distance to stop

13. Explain how gravity affects your vehicle.
OBJECTIVE

14. Gravity
Gravity is the force that pulls all things to Earth. Gravity also acts on you and your car, causing your vehicle to lose or gain speed.
What effect does gravity have on your car when driving uphill? Downhill?

15. How can you control speed if you were driving on this downhill stretch?

16. lesson 9.1 review How does inertia affect your vehicle?
How does inertia affect the passengers in your vehicle?