Question

The useful power output of Bryan Allen, who flew a human-powered airplane across the English Channel on June 12th, 1979, was about 350 W. The propellor of the airplane was driven by the pilot's legs, using a bicycle-tyoed mechanism. Using the efficiency for legs (20%), calculate the food energy he needed for the 2.5-hour trip.

Answer 1

foodenergy*.25=350*timeinseconds

so figure the time in seconds in 2.5hrs

Your answer will be in joules. To get Food calories,

foodcalories=energyinjoules/4200 joules

Answer 2

62.5