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You are designing a ski jump ramp for the next Winter Olympics. Youneed to calculate the vertical height^ h from the starting gate to the bottom of the ramp. Theskiers push off hard with their ski poles at the start, just abovethe starting gate, so they typically have a speed of 2.0^m/s as they reach the gate. For safety, the skiersshould have a speed of no more than 30.0^m/s when they reach the bottom of the ramp. Youdetermine that for a 86.0^ kg skier with good form, friction and air resistance will dototal work of magnitude 4000^ J on him during his run down the slope.What is themaximum height ^h for which the maximum safe speed will not be exceeded?

User Match
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1 Answer

5 votes

Answer:


H = 50.5 m

Step-by-step explanation:

As we know by work energy theorem that work done by all forces is equal to change in kinetic energy

So we know that


W_f + W_g = \frac{1]{2}mv_f^2 - (1)/(2)mv_i^2

so we know that


W_f = -4000 J


v_f = 30 m/s


v_i = 2 m/s


m = 86 kg

now we have


mgH - 4000 = (1)/(2)(86)(30^2 - 2^2)


86(9.81)(H) - 4000 = 43(900 - 4)


H = 50.5 m

User Gnosophilon
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