Finding average resistive force

AI Thread Summary
To find the average resistive force on a diver who drops from a 10-meter tower and comes to rest 5 meters underwater, the kinetic energy (KE) upon hitting the water must first be calculated. The diver's initial potential energy (PE) converts to KE as he falls, and the work done by the resistive force can be determined from the distance he travels underwater. The key equations involve the conservation of energy, where the initial energy equals the final energy plus work done against resistive forces. Understanding these concepts is essential to solve for the average resistive force exerted by the water.
jman1209
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I really need help with this!

Homework Statement


A 70-kg diver steps off a 10-m tower and drops from rest strait down into the water. If he comes to rest 5.0 m beneath the surface, determine the average resistive force exerted on him by the water.

Homework Equations


This is the only equation that I know goes with this problem:
(KE + PEg + PEs)i = (KE + PEg + PEs)f

The Attempt at a Solution


I can't get anywhere with this.
 
Physics news on Phys.org
What's the diver's KE when he hits the water? What's his KE when he comes to a stop? How much work was done stopping him? How do you calculate work?
 

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