The weight watcher must climb : 3.45 km to work off the equivalent of a large piece of chocolate cake rated at 670 calories.
First step : convert the energy to joules
670 calories to Joules
E = 670 * 10³ * 4.184
= 2803280 J
Next step : Equate energy to gravitational potential energy
2803280 J = mgh
2803280 = 82.9 * 9.8 * h
Therefore :
h = 2803280 / ( 812.42 )
= 3451 m = 3.45 Km
Hence we can conclude that The weight watcher must climb : 3.45 km
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