1. Write to Think 124 What is inertia? What is velocity?
Use your ALL resources to help you
On lined paper…
What is inertia?
What is velocity?
How do the two ‘combine’ to keep the Earth revolving around the sun?

2. Inertia
Newton’s 1st law (inertia) talks about an objects tendency to resist change.
Object in motion will stay in motion …
Object at rest will stay still …
UNLESS acted on by an unbalanced force!
A baseball flying forward continues to do so until it is acted on by an unbalanced force… gravity.
So …

3. Velocity
Force of Gravity

4. Velocity
Force of Gravity
Velocity
Force of Gravity
Force of Gravity
Velocity
Force of Gravity
Velocity

5. Truth or Myth Alert!
The Moon is constantly falling towards Earth.

6. Truth or Myth Alert! The Moon is constantly falling towards Earth.
TRUE!

7. Explaining Earth’s movement in space
Describe Earth’s Axis. How do we know it is there?
What is ‘rotation’? How does Earth demonstrate ‘rotation’?
How long does 1 rotation of Earth take?
How does Earth’s rotation influence our lives?
What is ‘revolution’? How does Earth demonstrate ‘revolution’?
How long does 1 revolution of Earth around the sun take?
How does Earth’s revolution influence our lives?
Describe the revolution of the moon around planet Earth.
How does the moon’s revolution influence our lives?
What is gravity?
Describe how the gravitational force between objects is affected by their mass.
Describe how the gravitational force between objects is affected by the distance between them.
Which is pulling on the other more, the Earth on the sun or the sun on the Earth?
Explain your answer to question 13.
What is an orbit?
What shape does Earth’s orbit take?
What is velocity?
What is inertia?
Explain how velocity and inertia play a role in planet orbits. Hint: objects traveling in motion stay in motion. Think baseball!
If the moon is constantly falling toward Earth than what keeps it from falling INTO Earth?

8. Newton’s 3rd law!

9. Newton’s 3rd law!

10. End of lesson

12. Rotation
23.5 degrees

13. Revolution

14. The sun, if thought of a single thing, does NOT have a gravitation force (pull)!?
How is this possible?

15. If the sun was the only object in the universe it wouldn’t have a gravitation force (pull).
A second object needs to be present for a gravitation force to exist, because gravity is generated by matter interacting with each other. ?

16. If the sun was the only object in the universe it wouldn’t have a gravitation force (pull).
A second object needs to be present for a gravitation force to exist, because gravity is generated by matter interacting with each other.
According to Newton’s 3rd Law, the two objects are pulling on each other with the same amount of force.

17. When either one of the objects gets larger then the gravitational force between them increases.
When either one of the objects gets smaller then the gravitational force between them decreases.

18. When either one gets closer to the other then their gravitational force increases.
When either one gets farther apart then their gravitational force decreases.