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I did a calculation to see how high the energy in a cell phone battery could lift an adult assuming perfect efficiency but something seems way off.

12Wh = 43,200J
43,200J / 90kg / 9.8m/s = 49m = 160ft

Another way to look at this is 12Wh = 10.3kcal (i.e. "calories") to climb 160ft or 80 calories to climb the 1250ft Empire State Building.

Are these calculations correct? The ratio of height to energy seems way off, or is it just that in reality you'll have a large inefficiency factor to achieve the work and then the numbers will seem more realistic if applying that?

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Your calculation is correct, and if you do it by climbing you accelerate an decelerate at every step, it is really very ineffective . So better think of pulling up the 90kg over a suspended wheel, or a pulley.

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