1. Universal Gravitation

2. Gravity Isaac Newton is first credited for the idea of mass being attracted to other mass. He saw the moon after the famous apple fell from the tree and decided both are in motion because of the Earth’s gravity

3. Gravity

5. The reason why the Moon doesn’t fall into the Earth, or the planets aren’t forced into the Sun is because of Newton’s 1 st law. These objects are traveling at the escape velocity of the bigger object, so that they try to maintain motion in a straight line but the gravity of the bigger object tries to pull them in, so they move in a circle.

6. Gravity

7. Remember that weight is relative. If you are in an accelerating frame, your weight can change. If you are in the center of a shell of mass, (and no where near the Earth) you will NOT feel any force of gravity. Ocean tides are caused by the Moon pulling on the Earth’s oceans.

9. Gravity Worksheet problems

10. Gravity Albert Einstein’s Theory of General Relativity solved many of the problems that Newton’s theory couldn’t. He considered the idea that space time is a grid. Mass creates dips in the grid.

11. Gravity Video on Newton vs Einstein

12. Gravity A black hole is a incredibly compact object where not even light can escape from it. Therefore it has an escape velocity equal to the speed of light Consider it a hole in the space- time grid in Einstein's theory.

13. Gravity Derivation of the Schwarzschild Radius

14. Gravity Book Problems: Pg 180 #7, 9, 11, 15, 22 Pg 196 #6, 20, 25