How do you calculate the amount of work it takes for a person to rotate the wheel of a bicycle once?

Question

Is it different for a low bicycle gear or a high bicycle gear?

Answer 1

Work  is just a term for energy.

The simplest formula for work is work =force x distance. This can get a bit confusing Work, energy and torque are all basically the same thing

If you know the force you need to move the bicycle then the work for one rotation will equal that force x the circumference of the wheel.(2.096 metres,6.88 feet for a 23x700c rim)

If you need to calculate the force then the formula you will need can be found on this link.

http://www.bikesatwork.com/hauling-cargo...

Typically a bicycle moving at a speed of 32 km/h (20 mph) (flat ground no wind) would use about 47 Joules (0.011 Calories,34.7 Foot pounds) per revolution. At 24km/h (15mph) it would only use about half this energy.

Work should be very close to the same for any given speed no matter which gear is selected.

Answer 2

It shouldn't matter what gear you're in. A higher gear results in more resistance on the pedal but fewer repetitions; a lower gear has less resistance, but more repetition: these ultimately equal out. The bigger question is the size of the rider and the speed the rider is traveling. It takes more watts (the standard measurement of a cyclist power) for a 200 lbs. rider to go 25 mph than it does for a 150 lbs. cyclist to do 25 mph. So there is a way to figure this out on an individual basis, but we would need a lot more info.