# Average force in a collision problem

1. Nov 14, 2007

### KatieLynn

1. The problem statement, all variables and given/known data

A 59.8kg ice skater, moving at 14 m/s crashes into a stationary skater of equal mass. After the collision, the two skaters move as a unit at 7 m/s. Suppose the average force a skater can experience without breaking a bone is 4640N. If the impact time is 0.047s, what is the magnitude of the average force each skate experiences?

2. Relevant equations

impulse = change in momentum
change in momentum= m(Vf-Vi)
impulse=Faverage(change in time)

3. The attempt at a solution

Honestly, I'm not sure where to begin but I'll give it my best shot...

I'm going to try this

impulse = Faverage(change in time)

so impulse = 4640N (.047s) = 218.08 ...I don't think thats anywhere near what this problem is asking for though...

2. Nov 15, 2007

### Shooting Star

The change in momentum of the 1st skater is known, which is equal to impulse = Fav x time. Then you can find Fav.