# physics again...

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A 62.0 kg diver falls from rest into a swimming pool from a height of 3.50 m. It takes 1.92 s for the diver to stop after entering the water. Find the magnitude of the average force exerted on the diver during that time.

• physics again... - ,

First, calculate the velocity when he hits the water using:

V(f)^2 = V(o)^2 + 2as

Then, calculate the deceleration as he goes through the water using:

V(f) = V(o) + at.

Then you can get the force once you know a with F = ma.

• physics again... - ,

they want us to use the height somehow.

• physics again... - ,

yes, in my first equation, the "s" is distance, or in this case, height.

• physics again... - ,

yeah its still not working i did that i think it wants us to more of an kinetic energy or work method to solve for it.

• physics again... - ,

OK, you can do it that way. First, he has potential energy = mgh. This gets converted into kinetic energy. The kinetic energy when he hits the water is (mv^2)/2, so you can calculate his velocity when he hits the water. Then calculate his deceleration, and the force.

• physics again... - ,

thanks!

• physics again... - ,

you're welcome!