What Power Output is Needed for a Bicyclist to Overcome Drag and Friction?

AI Thread Summary
To determine the power output needed for a touring bicyclist to maintain a speed of 11.7 m/s on a level road, the total force must account for both drag and rolling friction. The drag force is calculated using the drag coefficient, frontal area, and air density, while the rolling friction is based on the rider's and bike's mass. The initial calculation yielded a power output of 459.6W, but this was deemed incorrect. A more precise calculation is suggested to achieve an accurate result. Ultimately, the discussion emphasizes the importance of precision in calculations for determining the necessary power output.
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Homework Statement



For a touring bicyclist the drag coefficient C(where f of air = 0.5CApv^2) is 1.04, the frontal area A is 0.462 , and the coefficient of rolling friction is 4.60×10−3. The rider has mass 53.0kg, and her bike has mass 11.1kg.
Note: p is density of air (1.2kg/m^3)

To maintain a speed of 11.7m/s on a level road, what must the rider's power output to the rear wheel be?

The attempt at a solution

Total force = friction force + drag force
Power = total force x velocity = 459.6W

which is not correct.
 
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I would calculate it the same way, but with more precision. I got an answer close but possibly enough dissimilar?
 

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