Ski Slope using Energy Conservation

AI Thread Summary
The discussion focuses on a physics problem involving energy conservation on a ski slope. The skier starts at a height on a 60-degree slope and launches off a ramp after a circular arc. The key equations involve gravitational potential energy (Ug = mgh) and kinetic energy (K = 0.5mv²). The main challenge is determining the initial potential energy without knowing the skier's mass, but it is noted that mass will cancel out in the calculations. The conversation also raises a question about how to determine the launch angle for the skier's trajectory after leaving the ramp.
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Homework Statement



It's been a great day of new, frictionless snow. Julie starts at the top of the 60 degree slope shown in the figure . At the bottom, a circular arc carries her through a 90 turn, and she then launches off a 3.0--high ramp. How far horizontally is her touchdown point from the end of the ramp?

10.P49.jpg


Homework Equations



Ug = mgh
K = 0.5mv2
Kinematics equations

The Attempt at a Solution



I know I need to use energy conservation to find the kinetic energy at the end of the ramp so I can find the velocity of the skier then, but I do not know how I can find Ug at the top of the ramp without knowing the skier's mass (too many unknowns). Once I know the initial Ug or Kmax I know how to solve the problem, but I'm having trouble getting there.
 
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Never mind the mass, it will cancel. Just use m for the mass or any number you like.

ehild
 
Thanks ehild, got it.
 
Just wondering how the launch angle is determined in this question?
 

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