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### Weightlessness and Orbital.motion

1. WEIGHTLESSNESS AND ORBITAL MOTION © Simon Porter 2007
2. CONCLUSION QUESTIONS 1-5
3. CONCLUSION QUESTIONS 6-10
4. WEIGHTLESSNESS Weightlessness – free from the effects of gravity (Zero g) A sensation experienced by an individual when there are no contact forces acting on that individual. An example is when in a state of free-fall. Gravity and Inertia CREATE sensation of Weightlessness
5. ELEVATOR FUN!
6. WEIGHTLESSNESS So there is a force of gravity on the astronaut, but no reaction force from the floor so the astronaut feels weightless. © Simon Porter 2007 YouTube - flying dog YouTube - Greg Olsen - Drinking water on the ISS YouTube - Zero G Puke Bag
7. DRINKING WATER – ISS (GREG OLSEN)
8. ORBITAL MOTION  A result of the combination of an objects forward inertia and the downward pull of gravity.
9. ORBITING SATELLITES •Since Earth is CURVED, objects with enough inertia will stay in a state of freefall, orbiting Earth, creating the sensation of weightlessness.
10. KEEPING THE WORLD SAFE FROM MR. HASTINGS DOG! From a table, medium kick.
11. HOW FAR CAN YOU KICK A DOG? Gravity
12. HARDER KICK?
13. HARDER KICK Gravity
14. SMALL CANNON? Woof! (help)
15. SMALL CANNON Gravity Woof! (help)
16. BIGGER CANNON?
17. BIGGER CANNON Gravity Gravity
18. EVEN BIGGER CANNON?
19. EVEN BIGGER CANNON Gravity Gravity Gravity
20. VERY BIG CANNON?
21. VERY BIG CANNON Gravity
22. HUMUNGOUS CANNON?
23. DOG IN ORBIT! The dog is now in orbit! (assuming no air resistance of course)
24. DOG IN ORBIT! The dog is falling towards the earth, but never gets there!
25. DOGS IN ORBIT! The force that keeps an object moving in a circle is called the centripetal force (here provided by gravity) Gravity
26. Inertia and gravity combine to keep Earth in orbit around the sun and the moon in orbit around the Earth. A combination of gravity and inertia keeps the moon in orbit around the Earth. WHY DO EARTH AND THE MOON REMAIN IN THEIR ORBITS? If there were no gravity, inertia would cause the moon to travel in a straight line. If only gravity existed, the earth would be pulled into the sun.
27. DESCRIBE WHY AN ASTRONAUT WOULD FEEL WEIGHTLESS.
28. DRAW A DIAGRAM OF EARTH ORBITING THE SUN (LABEL FORCE ARROWS)