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clope023
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[SOLVED] Height of a Ski Ramp
You are designing a ski jump ramp for the next Winter Olympics. You need to calculate the vertical height h from the starting gate to the bottom of the ramp. The skiers push off hard with their ski poles at the start, just above the starting gate, so they typically have a speed of 2.0 m/s as they reach the gate. For safety, the skiers should have a speed of no more than 30.0 m/s when they reach the bottom of the ramp. You determine that for a 80.0 kg skier with good form, friction and air resistance will do total work of magnitude 4000 J on him during his run down the slope.
v1 = 2m/s
v2 = 30m/s
Ugrav1 = mgh
Ugrav2 = 0
K1 = 1/2mv1^2
K2 = 1/2mv2^2
Wother = 4000J
K1 + Ugrav1 + Wother = K2 + Ugrav2
(1/2(80)(2^2)) + (80(9.8))h + 4000J = (1/2(80)(30^2))
h = ((1/2(80)(30^2))-(1/2(80)(2^2)) - 4000J)/(80(9.8)) = 41m wrong
not sure what I did wrong, I'm sure I'm using the right equations, any help is appreciated.
Homework Statement
You are designing a ski jump ramp for the next Winter Olympics. You need to calculate the vertical height h from the starting gate to the bottom of the ramp. The skiers push off hard with their ski poles at the start, just above the starting gate, so they typically have a speed of 2.0 m/s as they reach the gate. For safety, the skiers should have a speed of no more than 30.0 m/s when they reach the bottom of the ramp. You determine that for a 80.0 kg skier with good form, friction and air resistance will do total work of magnitude 4000 J on him during his run down the slope.
Homework Equations
v1 = 2m/s
v2 = 30m/s
Ugrav1 = mgh
Ugrav2 = 0
K1 = 1/2mv1^2
K2 = 1/2mv2^2
Wother = 4000J
K1 + Ugrav1 + Wother = K2 + Ugrav2
The Attempt at a Solution
(1/2(80)(2^2)) + (80(9.8))h + 4000J = (1/2(80)(30^2))
h = ((1/2(80)(30^2))-(1/2(80)(2^2)) - 4000J)/(80(9.8)) = 41m wrong
not sure what I did wrong, I'm sure I'm using the right equations, any help is appreciated.