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Destructo_Dav
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Homework Statement
A 78kg man, standing erect, steps off a 2.6m high diving platform and begins to fall from rest. The man comes to rest 1.7s after reaching the water.
The acceleration of gravity is 9.8 m/s^2
What average force did the water exert on him?
Answer: 1091.94 N
Homework Equations
F= (deltaP)/(deltaT)
2x=gt^2
v=d/t
The Attempt at a Solution
The first mistake I made was using 1.7s as the time until the man hit the water to find the velocity at the moment before the man hits the water (v = 2.6/1.7), but this got me no where.
I think I need to find the time between when the man jumps and after he falls 2.6m later. I don't know of a way to dervie velocity from only having the distance one falls and the acceleration of gravity. Once I do find that I think I can get the initial velocity and the final velocity, and then I can use the momentum equation to find out the average force exerted. The answer was given to me, but I need to know and understand the process to get it for the test. Anyone have any ideas?