4.30) The useful power output of Bryan Allen, who flew a human-powered airplane across the English Channel on June 12, 1979, was about 350 W. The propeller of the airplane was driven by the pilot's legs, using a bicycle-type drive mechanism. Using the efficiency for legs given in Table 4.3, calculate the food energy he needed for the 2.5 hour trip. (The efficiency according in the Table 4.3 for legs in cycling is 20%)
Note: Guys please me..... Provide me an answer with solution/formula. Thanks!
To calculate the food energy needed for the 2.5 hour trip, we can use the formula:
Food energy = Useful power output / Efficiency
Given that the useful power output is 350 W and the efficiency for legs in cycling is 20% (0.20), we can substitute these values into the formula:
Food energy = 350 W / 0.20
Food energy = 1750 J/s / 0.20
Food energy = 8750 J
Since the formula gives us energy per second (J/s), we need to multiply it by the total time of the trip to get the total food energy. In this case, the trip lasted 2.5 hours, which is equal to 2.5 * 3600 seconds (3600 seconds in an hour).
Total food energy = 8750 J/s * 2.5 * 3600 s
Total food energy = 7875000 J
Therefore, Bryan Allen needed approximately 7,875,000 Joules (J) of food energy for his 2.5 hour trip across the English Channel.