1. Objective: Relate density to the relative positioning of Earth’s atmosphere, water, crust, and interior.

2. 1. How did the solar system form? -Nebula-gas, ice and dust -Gravity pulled materials closer -Nebula shrank/flattened to a disk -Disk begins to rotate -Materials in center become dense from outside pressure. -Sun is formed

4. How did the Solar System Form? - Nebula-gas, ice and dust -Gravity pulled materials closer -Nebula shrank/flattened to a disk -Disk begins to rotate -Materials in center become dense from outside pressure. -Sun is formed

5. 2. What caused them to come together? -Gravity is the force that every object exerts on all other objects because of their masses. -Mass and distance are the factors. GRAVITY Earth’s Structure, Lesson 1, Review, Personal Tutor, Gravity

6. 3.Which object has a stronger gravitational force? A. B.

7. 4. All four objects have the same mass. Which row has the weakest gravitational force between them? A B

8. A B C D E 5. Which planet pair would have the greatest amount of gravitational pull between them? 6. Which planet pair would have the least amount of gravitational pull between them?

9. 7. Why does Earth exert a greater gravitational force on you than other objects like the sun?

11. Earth has more mass than any object near you. It exerts a greater gravitational force on you than other objects do. You don’t notice the gravitational force between less massive objects.

12. 8. Which object in the solar system exerts the most gravitational pull on all the other objects, and why?

13. The sun. It has the most mass of all the matter in our solar system.

14. 9. How are the planets shaped during Earth’s Final Formation?

15. -Planets shape from remaining bits of material.

16. - Earth formed as gravity pulled these small particles together -Particles stick in uneven shapes as they collide -The larger mass particles attracted more particles -Continued to grow large

17. -Generated thermal energy inside from the surrounding pressure -Particles inside melt and flow -Gravity pulls in irregular bumps

18. 10. How were Earth’s layers created? -Collisions created a mass of solid particles -Thermal energy from within began to flow -Distinct layers formed based on Density -More dense toward the center, less dense toward the outside

19. 11. Relate the Earth’s formation by this experiment: Put an iron block and a pinewood block with the same volumes in a beaker of water. Which will float on the surface and which will be pulled through the water to the bottom of the beaker by gravity?

20. -There is a stronger gravitational force between Earth and a denser object than there is between Earth and a less dense object.

21. -When ancient Earth started melting, the densest materials sank and formed the innermost layer of Earth. -The least dense materials stayed at the surface and formed a separate layer. Earth’s Structure, Lesson 2, video, What’s Inside.

22. Pulling it all together videoclip: Earth’s Structure, Lesson 2, Review, Personal Tutor, Density

23. Credits Astronomy online http://astronomyonline.org/SolarSystem/SolarSystemFor mation.asp Mail Online http://www.dailymail.co.uk/sciencetech/article- 2034667/Earths-gold-platinum-arrived-meteor-shower- lasting-200MILLION-years.html