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← 03-18 Solving for Acceleration

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

  1. These equations are definitions of velocity and acceleration,
  2. but we can also use them to make some calculations.
  3. For example, let’s suppose I drop a ball 5 meters and it takes 1 second for this ball to fall.
  4. For example, let's say I drop a ball 5 meters and I measured
  5. that it takes 1 second for the ball to hit the ground.
  6. What was the ball’s average velocity?
  7. And we will talk more about more why I’m using the word “average” later.
  8. Δx is change in position, how much is ball’s position changing?
  9. Well, it's changing by 5 meters.
  10. V equals change in position--5 meters--over change in time--well, it took 1 second.
  11. So, 5/1 is just 5 meters per second. Not bad. Now, how about you do one.
  12. Let’s say that Galileo drops a ball at the Leaning Tower of Pisa
  13. and he finds that after 2 seconds, it’s speed is 20 meters per second.
  14. I want you to tell me what was the ball’s acceleration.