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This is a projectile motion problem at a Grade 12 level in Canada.

My main problem here is conceptual, not the math itself.

A diver takes off with a speed of 8.0m/s from a 3.0-m high diving board at 30

My diagram:

[PLAIN]http://img830.imageshack.us/img830/3949/diagram.jpg [Broken]

I was given the solution to use the equation

[PLAIN]http://img294.imageshack.us/img294/1028/worky.jpg [Broken] [Broken]

I don't understand why the solution would work, or more precisely, be complete. From how I understand it, the solution would give the answer for just the red highlighted part in the projectile trail of this picture:

[PLAIN]http://img638.imageshack.us/img638/1486/diagram2b.jpg [Broken]

Since the equation had distance (Or is it displacement?) = 3m, I think that it did not include anything above the diving board. Am I wrong here?

----------------------Alternative---------------------------

[PLAIN]http://img205.imageshack.us/img205/1645/diagram3.jpg [Broken]

If I were given this situation, would I still arrive at the same answer with the same process as this? [PLAIN]http://img294.imageshack.us/img294/1028/worky.jpg [Broken] [Broken]

I hope I have described my problem well enough, any help would be appreciated!

Thanks!

My main problem here is conceptual, not the math itself.

**1. The given question**A diver takes off with a speed of 8.0m/s from a 3.0-m high diving board at 30

^{o}above the horizontal. How much later does she strike the water?My diagram:

[PLAIN]http://img830.imageshack.us/img830/3949/diagram.jpg [Broken]

**2. The solution given**I was given the solution to use the equation

**d = v**and solve for t, which would end up in the form of the Quadratic formula. The answer given is 1.3s._{0}t + 0.5at^{2}[PLAIN]http://img294.imageshack.us/img294/1028/worky.jpg [Broken] [Broken]

**3. What I don't understand**I don't understand why the solution would work, or more precisely, be complete. From how I understand it, the solution would give the answer for just the red highlighted part in the projectile trail of this picture:

[PLAIN]http://img638.imageshack.us/img638/1486/diagram2b.jpg [Broken]

Since the equation had distance (Or is it displacement?) = 3m, I think that it did not include anything above the diving board. Am I wrong here?

----------------------Alternative---------------------------

[PLAIN]http://img205.imageshack.us/img205/1645/diagram3.jpg [Broken]

If I were given this situation, would I still arrive at the same answer with the same process as this? [PLAIN]http://img294.imageshack.us/img294/1028/worky.jpg [Broken] [Broken]

I hope I have described my problem well enough, any help would be appreciated!

Thanks!

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