Stuntman jumping 2D kinematics.

AI Thread Summary
A stuntman jumps from building A to building B, which is 0.9m shorter, with a flight time of 1 second at a 30-degree angle. To find the horizontal distance covered, the equation x = cos(30) * Vo * 1s is used, while the vertical displacement equation requires adjusting the initial vertical position to 0.9m. The correct form for vertical displacement is y(t) = y0 + Vo * t - (1/2)gt^2, with y0 set to 0.9m. This adjustment allows for the calculation of the stuntman's initial speed Vo and subsequent horizontal distance. The discussion emphasizes the importance of accurately defining initial conditions in kinematic equations.
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Homework Statement


A stuntman is jumping from building A to building B. His flight lasts 1s. He leaves point A with a speed of Vo at an angle of 30 degrees above horizontal. Building B is .9m shorter than building A. What horizontal distance was covered by the stuntman given he makes it to the very edge of building B? What was the maximum height with respect to the starting point attained by the stuntman?


Homework Equations


Displacement and velocity kinematic equations.


The Attempt at a Solution


displacement x= cos(30)*Vo*1s
displacement y= sin(30)*vo+.5(-9.8)(1)-.9m

I know that somehow i need to find Vo from the Y data then plug it into the x displacement equation but i am not sure how this is going to be possible with the given information.
 
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Your equation giving y has an incorrect value for the initial vertical position. The general form is

y(t) = y0 + voyt - (1/2)g t2

What is the value for y0? In other words, if you plug in t=0 in the above equation, what should y0 be so that it matches the vertical position of the stuntman?
 
oh should it be a +.9 since at t=0 he is .9 above where he will end up?
 
Yes. So his initial vertical position is 0.9 m and his final vertical position is 0 m. Now you can put the equation together.
 
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