SOLUTION: What is the potential energy of a 72 kg person sitting on a ladder2 m off the ground? (Write out the unit)

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Question 751231: What is the potential energy of a 72 kg person sitting on a ladder2 m off the ground? (Write out the unit)
Answer by Edwin McCravy(20065) About Me  (Show Source):
You can put this solution on YOUR website!
PE = mgh  (the m is for mass in kg, not meters)

PE = (72kg)(9.8m%2Fs%5E2)2m   (the m's are for meters, not mass.)

PE = 1411.2kg%2Am%2Fs%5E2%22%22%2A%22%22m

And since 1 newton = 1N = 1%28kg%2Am%29%2Fs%5E2,

PE = 1411.2 N·m

and since 1 newton·meter = 1 N·m = 1 joule

PE = 1311.2 joules.

Edwin