Gravity Its not just a good idea Its

Gravity It’s not just a good idea. It’s the law!

I. Isaac Newton (1642 -1727) A. No, he didn’t discover gravity. 1. Everybody knew that it existed. 2. Newton quantified how it works. 3. He did the math.

B. Newton made the connection between: 1. the force that causes the apple to fall 2. the force that holds the moon in orbit

C. All objects with mass attract each other D. The strength of that force is determined by: 1. The mass of the objects 2. The inverse square of the distance a. if the distance doubles the force is 1/22 or 1/4 b. if the distance triples the force is 1/32 or 1/9

E. On Earth falling objects accelerate at 9. 8 m/s 2 Example: You drop a penny off the top of a building: 1. After 2 seconds it is moving at 2 s x 9. 8 m/s 2 = 19. 6 m/s 2. After 5 seconds it is moving at 5 s x 9. 8 m/s 2 = 49 m/s

F. Terminal Velocity 1. You jump off of the high dive: a. after 3 seconds you are moving at 3 s x 9. 8 m/s 2 = 29. 4 m/s b. after 6 seconds you are moving at 6 s x 9. 8 m/s 2 = 58. 8 m/s

2. as you fall air resistance is exerting an opposite force on you 3. the faster you fall the more force it puts on you 4. when the forces of gravity pulling down and air resistance pushing up are equal you stop accelerating 5. parachutes work by increasing air resistance so you reach terminal velocity at a lower speed

II. Albert Einstein (1879 -1955) A. Developed theory to explain why gravity works. B. Theorized that matter warps space/time

C. The greater the mass, the more it warps space D. This warping causes objects to move towards each other