2. 1) What is the name of the law about gravity? The law of… A) …Conservation of Mass or B) …universal Gravitation (2) All matter in the universe attracts other matter by? A) A “pushing force” or B) A “pulling force” (3) The amount of gravity depends on the _______ of the objects A) Shape or B) Masses 4) Effect of gravity depends on the _____ between the objects. A) Planets or B) Distance 5) What did Einstein say about mass and gravity? A) That mass warps space or B) Mass and gravity are the same SPI 0807.12.5 to 12.6 Gravity Bellwork Jan 8, 2013 1 PRESS THE RIGHT-ARROW BUTTON ON YOUR KEYBOARD TO ADVANCE THROUGH THE SLIDES!

3. 1)What is the name of the law about gravity? The law of… B) …universal gravitation 2) All matter in the universe attracts other matter by? B) A “pulling force” 3) The amount of gravity depends on the _______ of the objects B) Masses 4) Effect of gravity depends on the _____ between the objects. B) Distance 5) What did Einstein say about mass and gravity? A) That mass warps space SPI 0807.12.5 to 12.6 Gravity Bellwork 2

4. 1) Look at the two diagrams below. In the 1 st diagram two soccer balls are 5m apart. In the 2 nd diagram two soccer balls are 8m apart. In which diagram is the gravitational attraction greatest and why? Diagram 01 Diagram 02 SPI 0807.12.5 to 12.6 Gravity Notes 1 5 meters 8 meters WHY?: Because the effect of gravity is greater when objects are closer together

5. Newton discovered the law of universal gravitation. Einstein theorized that mass warps/bends/curves space and this warping explains the force we call gravity SPI 0807.12.5 to 12.6 Gravity Show A Youtube video: (1)Link: Curvature of Space Time (34 sec)Link: Curvature of Space Time (34 sec) (2)How Gravity Really WorksHow Gravity Really Works Demonstration:  Use a sheet and a soccer ball to demonstrate how gravity wraps the fabric of space 3 Notes

6. Earth’s Rotation and Revolution Gravity causes our planet to rotate on its own axis Gravity keeps our planet (and all the other planets) from “flying off” into space as it revolves (orbits) around the sun (Do demonstration of rotation vs. revolution) Notes SPI 0807.12.5 to 12.6 Gravity 4

7. Gravity and the Motion of the Moon Gravity keeps the moon from “flying off” as it revolves (orbits) the Earth (See Holt Online Ch15: Sect 4 Visual Concepts)  VC about gravity and orbits SPI 0807.12.5 to 12.6 Gravity Notes 5

8. 1) What is one way gravity helped form our solar system and planets? A) By pulling matter together B) By pushing matter apart 2) What is another way gravity helped form our solar system and planets? A) By making objects revolve and rotate B) By making objects move in straight lines 3) Contrast revolution and rotation A) Revolve=moving around another object, Rotate=spinning on an axis B) Revolving is faster than rotation and has more gravity SPI 0807.12.5 to 12.6 Gravity Review 6