Jumping on a sliding board with no friction between surfaces.

AI Thread Summary
To jump from one end of a frictionless board to the other, the jumper must consider both their take-off speed and the board's reaction. The board will move backward as the jumper pushes off, affecting the jump's trajectory. The jumper's speed relative to the pond must account for both the horizontal and vertical components of the jump. The time in the air and the board's backward speed are crucial for determining the minimum required take-off speed. Ultimately, the solution involves calculating the relationship between these variables to ensure a successful jump across the board.
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Homework Statement



You stand at the end of a long board of length L. The board rests on a frictionless frozen surface of a pond. You want to jump to the opposite end of the board. What is the minimum take-off speed v measured with respect to the pond that would allow you to accomplish that? The board and you have the same mass m.

What is v?

Homework Equations





The Attempt at a Solution



Since there is no friction, on attempt of jumping, the skateboard is going to move back some distance. How do I find the distance and relate to the velocity? Clueless about this problem
 
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Just to be clear, I assume that you jump with a velocity and an angle with respect to the board, yes?
 
Suppose you take off at speed v, relative to the pond, and angle theta to the horizontal. What will be the vertical and horizontal components of your speed? How long will you be in the air? What horizontal speed did the board get? What then is your horizontal speed relative to the board?
 
sqrt(g*L/2)
 
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