- #1
Whotto
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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.
1. The given question
A diver takes off with a speed of 8.0m/s from a 3.0-m high diving board at 30o above the horizontal. How much later does she strike the water?
My diagram:
[PLAIN]http://img830.imageshack.us/img830/3949/diagram.jpg
2. The solution given
I was given the solution to use the equation d = v0t + 0.5at2 and solve for t, which would end up in the form of the Quadratic formula. The answer given is 1.3s.
[PLAIN]http://img294.imageshack.us/img294/1028/worky.jpg
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
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
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
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 30o above the horizontal. How much later does she strike the water?
My diagram:
[PLAIN]http://img830.imageshack.us/img830/3949/diagram.jpg
2. The solution given
I was given the solution to use the equation d = v0t + 0.5at2 and solve for t, which would end up in the form of the Quadratic formula. The answer given is 1.3s.
[PLAIN]http://img294.imageshack.us/img294/1028/worky.jpg
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
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
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
I hope I have described my problem well enough, any help would be appreciated!
Thanks!
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