## ← 06-21 Why No Work?

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Showing Revision 1 created 07/23/2012 by Amara Bot.

1. Why was there no work done in the previous example? What happened?
2. Well, our definition of work, this is the product of a force and Δx, a distance.
3. Well here, while I'm holding my 5 kg bucket, I'm definitely exerting a force of 50 N
4. and I exerted over a distance of 4 m.
5. Why is the answer not 50 * 4? Well, the reason is I was dishonest with you.
6. I need to give you a little more instruction on how to use this equation.
7. Noticed that when I write force, I have to write 50 N that's the size
8. but I write an up arrow to represent the direction.
9. When I write Δx, 4 m is the distance, but that distance was to the right.
10. Both of these quantities have both a size 50, 4,
11. and the direction upward to the right, associate with them.
12. When I make this multiplication, I have to very careful on how I do it.
13. Specifically, I have to take what I'm going to call the parallel component of force with the distance.
14. Now, this idea of parallel component is a little hard to explain and a little hard to understand at first.
15. Why don't we go ahead and do an example and I think you'll see what I mean.