Question

A piece of chocolate cake contains about 400 calories. a nutritional calorie is equal to 1000 calories (thermochemical calories), which is equal to 4.184 kj. how many 8 inch high steps must a 180 lb man climb to expend the 400 cal from the piece of cake? see #26 for the formula for potential energy.

Answer 1

PE = mgh
solve for h:
PE = 1673600.J  

m = 180 lb (.4536 kg/1 lb) = 81.648 kg 
g = 9.8 m^2/s^2  
h = x = 800.1504 m (39.37 in/m) = 82346.555 inch 

Steps = 82346.555 inch (1 step / 8 inch) = 10,296.32 steps

Note: Percent daily values are based on a 2000 calorie diet. If only 10 steps per 400 cal than he must be a 100 foot tall man weighing about 2500 lbs something like that.