posted by Student B .
A 735 N person walks up three flights of stairs, covering a total vertical distance of 10.0 m. If, as is typical, only 20.0% of the caloric (food) energy is converted to work by the muscles, how many joules and food calories of energy did the person use? (One food calorie 4186 J.)
Five times the energy needed to climb the stairs. That would be 5 x 735 x 10 Joules.
Convert that to food calories using the conversion factor provided.