(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

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

2. Relevant equations

F= (deltaP)/(deltaT)

2x=gt^2

v=d/t

3. 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?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: An Erect Man Falls Into Water from a Platform

**Physics Forums | Science Articles, Homework Help, Discussion**