1. TODAY 1) Over the weekend/next class: Video up on new information.

2. TO INFINITY…AND BEYOND! Lets look at rockets for a moment. How in the heck do they work? When they work… How did the rocket go up?

3. ROCKET SCIENCE, BABY! How the rocket went up…. Lets draw a FBD with a net force equation: But where is this force coming from? The ignition of the fuel pushed gas out, which creates an opposite force pushing the rocket up.

4. Q UESTION F OR Y OU A LL As it’s going up, should the velocity of the rocket increase/decrease or not change if the thrust (engine force) is constant?

5. OH GOD, ROCKET SCIENCE So as getting further from Earth, the weight decreases. The rocket gets lighter too, so it has less mass for the imbalance to accelerate. More imbalance, less mass to accelerate means more acceleration!

6. B UT NOT EVERYONE AGREED

7. B UT IT TURNS OUT IT WORKS Newtons laws don’t need atmospheric pressures (atm’s) to work. In outer space, we are in micro-gravity don’t you mean zero gravity? So you are working on the ISS, and you turn a valve clockwise. What happens to you? Yeah, you get it. NASA didn’t at 1 st

8. So Newton’s laws work anywhere in the universe* They will form the basis of how we study motion in almost every situation. Blocks on ramps Masses with pulleys Planets around stars and why they don’t get sucked into the star* Ice skaters in routines and why they speed up when their arms go in Bicycle riders and why they don’t fall over if they start moving. Why running on pavement results in a faster run (but is more painful on your knees)

9. T HE P HYSICS OF THE R UN Run definition: Both feet off the ground. FBD of person of them before they start running.

10. T HE P HYSICS OF THE R UN Run definition: Both feet off the ground. FBD of person of them as they push off…

11. There is no normal force if you left the ground (since you are pushing up and off) Which is greater, the weight or the force of them pushing up? There is an imbalance on them, which by Newtons 2 nd Law creates an acceleration. IN THIS CASE…

12. W HEN YOU COME BACK DOWN TO GROUND You are moving down and then come to a stop. Is there an imbalance? 1 st lets draw a FBD of the person hitting the ground IMBALANCE UP, since you are SLOWING your downwards motion.

13. WHEN HITTING THE GROUND If the imbalance is UP, which has more force; the UP or DOWN force? Our net force equations: Where do we feel this force?

14. EVEN IN SPACE It all ties in together. Water in space… The water molecules all pull on eachother until they equalize into a max volume/min surface area arrangement: A sphere. Which mimicks planet formation in a special way, and possibly the first cellular life. Oh yeah

15. A N EXAMPLE … A panda is lifting a 10kg child up at a constant velocity. How much force is he applying to the child? Is there an imbalance? Is he lifting MORE/LESS/EQUAL to the weight?

16. A N EXAMPLE … A panda is lifting a 10kg child up, and is accelerating the child at 2m/s 2. How much force is he applying to the child? Is there an imbalance? Is he lifting MORE/LESS/EQUAL to the weight?

17. A N EXAMPLE … A panda is lifting a 10kg child up, but the child is slowing at a rate of 2m/s 2. How much force is he applying to the child? Is there an imbalance? Is he lifting MORE/LESS/EQUAL to the weight?

19. TO DA BOARDS.