Horizontal Projectile Motion Problem

temaire
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Homework Statement


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


Homework Equations


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

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 [tex]y = h - \frac{1}{2}gt^{2}[/tex] to solve for [tex]h[/tex], and I ended up with [tex]h=\frac{1}{2}gt^{2}[/tex]. I then used the formulas [tex]x=v_{o}t[/tex] and [tex]x = v_{o}\sqrt{\frac{2h}{g}}[/tex] to come up with the formula [tex]t = x\sqrt{\frac{2h}{g}}[/tex]. I then substituted this formula into [tex]y = h - \frac{1}{2}gt^{2}[/tex], made [tex]y=0[/tex] and simplified the equation until I got [tex]x=1[/tex]. So, now I know what the [tex]x[/tex] value is when [tex]y=0[/tex]. 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?
 
Last edited by a moderator:
on Phys.org
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 separately. 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 separately. 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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