Write to Think 123 Use your ALL resources to help you On lined paper… How does the gravitational force between two objects change as either of the objects increases in mass? How does the gravitational force between two objects change as the two objects get farther apart? Are the Earth and sun pulling on each other equally? If yes, then why doesn’t the sun orbit around the Earth? Is the moon constantly falling toward Earth? (this does not mean getting closer!)

Answers and Debrief of simulation Read the question Read your answer Compare with your lab partner Repeat for all questions Now check answer sheet!

CFU Questions … do you ‘get’ it? Everyone will participate! Point up or down to show how the gravitational force and relationship changes: Sun becomes more massive. Sun becomes less massive. Earth becomes more massive. Earth becomes less massive. They get closer. They get farther away. What happens to the velocity of the planet when it gets closer to the sun?

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 …

Velocity Force of Gravity

Velocity Force of Gravity Velocity Force of Gravity Force of Gravity Velocity Force of Gravity Velocity

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

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

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?

Newton’s 3rd law!

Newton’s 3rd law!

End of lesson

Rotation 23.5 degrees

Revolution

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

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. ?

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.

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.

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