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← 03-41 Initial Velocity

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Showing Revision 1 created 07/03/2012 by Amara Bot.

  1. Okay, so you have this amazing new skill, and you can calculate all sorts of motion problems.
  2. Now, can you calculate every motion problem?
  3. The answer is not quite yet.
  4. There are two types of problems we still can't solve.
  5. We can't solve problems where an object starts with some initial velocity,
  6. and we can't solve problems where the object moves in two dimensions,
  7. but we'll get to that later.
  8. For now let's talk about this initial velocity idea.
  9. The variable we're going to use to talk about initial velocity is V with the subscript 0.
  10. This comes from the idea that when we start a problem
  11. we usually start our timer at 0.
  12. So this is at time equals 0 what is the velocity?
  13. Let's think back to Galileo standing on top of the leaning tower of Pisa.
  14. This time around, instead of just having him drop the ball,
  15. let's imagine he could throw the ball straight down with different initial velocities.
  16. Now, just to get you thinking, I want to think about this question,
  17. when will the ball go farther?
  18. If he drops the ball with an initial speed of 0--so that's truly just dropping the ball
  19. and not throwing it at all--will the ball go farther then?
  20. Let's say in a single second?
  21. Or will the ball go farther if he throws it at 10 m/s straight down?
  22. In one second, when will the ball go farther?