Horizontal Projectile Motion Problem

AI Thread Summary
The discussion centers on a physics problem involving horizontal projectile motion, where a mountain climber jumps across a crevasse. The climber's landing angle and the height difference between the crevasse sides are key variables. The relevant equations include those for horizontal distance and vertical motion, leading to the conclusion that the height can be expressed as h = 0.5gt². Participants emphasize the importance of treating vertical and horizontal motions separately and note that without specific values, a unique solution for height cannot be determined. The consensus is that the height formula is valid, but the horizontal distance does not affect the height calculation.
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Homework Statement


A mountain climber jumps a crevasse by leaping horizontally with speed v_{o}. If the climber's direction of motion on landing is \Theta below the horizontal, what is the height difference h between the two sides of the crevasse?


Homework Equations


x=v_{o}t
v_{x}=v_{o}
y = h - \frac{1}{2}gt^{2}
v_{y}= -gt
v_{y}^{2} = -2g\Delta y
y = h - (\frac{g}{2v_{0}^{2}})x^{2}
x = v_{o}\sqrt{\frac{2h}{g}}

The Attempt at a Solution


I started off by drawing the following diagram:
http://img191.imageshack.us/img191/2616/physicss.jpg

Afterwards, I used the formula y = h - \frac{1}{2}gt^{2} to solve for h, and I ended up with h=\frac{1}{2}gt^{2}. I then used the formulas x=v_{o}t and x = v_{o}\sqrt{\frac{2h}{g}} to come up with the formula t = x\sqrt{\frac{2h}{g}}. I then substituted this formula into y = h - \frac{1}{2}gt^{2}, made y=0 and simplified the equation until I got x=1. So, now I know what the x value is when y=0. The problem is I'm stuck right here and don't know how to find the height. Can someone point me in the right direction please?
 
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You can't get a particular solution since you arent given any values. So h = 0.5gt^2 is correct.

Remember when dealing with these types of questions to work out the vertical and horizontal probelms seperately. The climber could have jumped 1m or 500m horizontally, but it wouldn't have changed how long he would have been in the air for nor the height of the crevasse.
 
Idyllic said:
You can't get a particular solution since you arent given any values. So h = 0.5gt^2 is correct.

Remember when dealing with these types of questions to work out the vertical and horizontal probelms seperately. The climber could have jumped 1m or 500m horizontally, but it wouldn't have changed how long he would have been in the air for nor the height of the crevasse.

So I shouldn't specify an x value in my answer?
 
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