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.

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.

bobpursley · Answer

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

Kelly · Answer

62.5