1. MOTION What is Motion?

2. §The world around you is on the move. Motion occurs whenever something changes place. It takes a force - a push or pull - to get something moving, and another force to make it change direction or stop.

3. §Most humans and animals have muscles that produce the force they need to move, while machines are powered by engines or motors.

4. §Objects move more easily on wheels. If you ride a skateboard, you can travel faster than your legs can carry you.

5. §Air and water are constantly moving. With a sail and a board, you can catch the wind and zoom across the waves.

6. §Salmon leap up a waterfall as they travel upstream to breed. Animals also move to find food and to escape from enemies.

7. §The powerful engine on a speeding train moves it faster than any other vehicle on land.

8. §When you play basketball, your muscles provide the force you need to run, leap, and shoot baskets.

9. §A hummingbird can beat its wings as fast as 80 times a second!

10. §Motion requires energy. A remote controlled car is powered by a motor that uses energy from a battery. People get energy from the food they eat.

11. §Sir Isaac Newton, a great scientist, put into effect three ideas that help us to understand motion better. The first one: An object at rest stays at rest; an object in motion stays in motion until it hits an outside force.

12. §Everything from the smallest atom to the largest sun is in motion. Newton’s first law is a description of the property of inertia. Inertia is the lazy property, it likes things to stay the same.

13. §If a rock is lying on the ground and you want to move it, you will find that it is harder to start moving the rock than it is to keep it moving. Inertia wants it to stay - it takes energy to move something.

14. §The motion of an object is very easy to measure. When something is moving, we are interested in how much distance is covered in what period of time. We like to measure things!

15. §Just as in a car race, we like to measure the speed of other objects as well. We measure how fast blocks fall when they are hit. And how fast a stack of pennies falls, also.

16. §If something is at rest, it wants to stay that way, so it takes lots of force to move it.

17. §If something is moving, it wants to remain moving at the same speed and in the same direction, so it takes another force to stop it or change its direction.