(adsbygoogle = window.adsbygoogle || []).push({}); 1. A 60 kg stuntperson runs off a cliff at 4.6 m/s and lands safely in the river 10.2 m below. What was the splashdown speed?

2. Relevant equations

PE = mgh

KE = (1/2)mv^2

PEi +KEi = PEf + KEf

(TMEi) = (TMEf)

3. The attempt at a solution

I really had no idea how to start this but this is what i did:

i used TMEi = TMEf where the mass would cancel out

so the equation you end up with would be

(60 kg)(9.8 m/s2)(10.2) + (1/2)(60 kg)(4.6 m/s)^2 = (1/2)(60kg)(v^2) << i don't think you have to add PEf to that because the height is zero

but i didn't get the right answer. i'm doing this for a webassign..

thanks for the help

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# Homework Help: What was the splashdown speed?

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