How to calc human bicycle power in watts

AI Thread Summary
To calculate Lance Armstrong's power output while cycling at 30 mph for 125 miles on level ground, one must consider the resistive forces such as friction and wind resistance, which impact energy consumption. The discussion highlights the need for specific equations to quantify these forces, as the initial information provided may be insufficient for accurate calculations. It is noted that maintaining a constant speed on a flat surface theoretically requires no energy, but practical scenarios involve various resistive factors. Additionally, there is a question regarding Armstrong's weight, suggesting a potential oversight in the initial parameters. Accurate calculations will require further details on resistive forces and possibly adjustments to the weight assumption.
Dyllon
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Homework Statement


How to calculate Lance Armstrongs power output/calorie consumption at 30 mph, 125 miles on level ground , no wind, 157 lbs plus 16lb bike?


Homework Equations

What equations do I use?



The Attempt at a Solution


I'm 14 years old, where do I start
 
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I don't think there's enough information given to do the calculation. The energy used will be a function of the resistive forces that have to be overcome by the cyclist. In an ideal world, traveling at constant speed on a flat track uses no energy, but in reality there's friction and wind resistance and other things also.

Doesn't Lance Armstrong weigh more that 157 lbs ?
 

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