Pole-Vaulter Landing on a Padded Surface

[sona1177]

Homework Statement

A pole vaulter vaults over the bar and falls onto thick padding. He lands with a speed of 9.8 m/s; the padding then brings him to a stop in a time of .40 seconds. What is the average force on his body due to the padding during this time interval? Express your answer as a fraction or multiple of his weight. Hint: The force due to padding is not the only force acting on the vaulter during the .40 second-interval.

Homework Equations

mdeltav=Fdeltat

The Attempt at a Solution

I have no idea. IM trying to use mdeltav/t=P-mg but this isn't giving me any insight into the force. HOw do I approach this?

 

[Redbelly98]

You're on the right track. The problem is that we need to know the pole vaulter's mass to solve this problem, and we don't have that information. This problem cannot be solved as written.