varsity
posted by karli .
A skydiver, with her gear, weighs 75 kg. She jumps from a helicopter at an altitude of 2 500 metres, waits 20 seconds and then opens her parachute. Assume that her initial velocity is zero, and also assume the following regarding air resistance: air resistance during freefall is proportional to the square of her velocity, with drag coefficient k1 = 0:1; air resistance with an open chute is proportional to her velocity (i.e. a linear relationship), with drag coefficient k2 = 22. How long will it take her to reach the ground?

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