Hitting a Wall

When a swimmer is coming in to the end of their race they have to prepare themselves, because to finish a race, the swimmer has to ram their hand into a concrete wall while moving as fast as they can.
The amount of force their arm must absorb as they go from a sprint to a dead stop is huge, and that is what we are going to figure out here.

   
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If the swimmer is moving 22.88m in 13.88s then

$$Velocity = 22.88m / 13.88s = 1.64 m/s

If $$xo is the distance of a swimmers shoulder to their fingertips right when they first make contact with the wall then xo${x}_{o}$ is 0.673m
If x is the distance of the swimmers shoulder to fingertips when they finally come to a stop then x is 0.537m
The time it took for the swimmer to touch the wall and come to a stop is 0.25s.

$$x = (xo) + (vo)t + 0.5at^2

The final position of an object is equal to the initial position plus the initial velocity multiplied by time plus half the acceleration multiplied by time squared

Using the above equation and plugging in our velocity and positions for x we get

$$0.537m = 0.673m + 1.64m/s(0.25s) + 0.5(a)(0.25s)^2

Solving for acceleration we get

Acceleration = -17.472 m/s^2

$$Plugging in our acceleration into our force equation we get that the force with which a swimmer hits the wall at the end of a race is about

$$F = ma = -17.427m/s^2(59.65kg) = 1039.52 N

This amount of force is a forth of the amount of force needed to break a femur.