## ← 05-19 An Accelerating Train Solution

• 1 Follower
• 19 Lines

### Get Embed Code x Embed video Use the following code to embed this video. See our usage guide for more details on embedding. Paste this in your document somewhere (closest to the closing body tag is preferable): ```<script type="text/javascript" src='https://amara.org/embedder-iframe'></script> ``` Paste this inside your HTML body, where you want to include the widget: ```<div class="amara-embed" data-url="http://www.youtube.com/watch?v=e-MtVwTa2B8" data-team="udacity"></div> ``` 2 Languages

Showing Revision 1 created 07/09/2012 by Amara Bot.

1. The answer is the apple will actually appear to move backwards.
2. Now, this was a tricky one, but you can verify it for yourself.
3. If you drive or if you know someone who does, get in the car, take an apple
4. and wait at a red light.
5. Once that light turns green, accelerate forwards and drop the apple.
6. You'll see that it actually appears to land behind where you released the apple from.
7. When we accelerate this way, the apple appears to move backwards.
8. When we accelerate that way, likewise. The apple moves backwards.
9. Of course, if you're going to do this, make sure you're safe about it
10. and make sure your car has wheels.
11. What's really interesting about what we found here
12. is that acceleration seems to be somehow important.
13. Objects at rest behave in the same way as objects moving at constant speed
14. but acceleration is important.
15. Things no longer behave the same when what we call our reference frame starts accelerating.
16. We also saw that acceleration was somehow special when we looked at Galileo
17. who found that all objects fall at a constant acceleration.
18. Clearly, acceleration is a very important quantity,
19. and by the end of today you will understand it very deeply.