Question

An athlete in a gym applies a constant force of 50 N to the pedals of a bicycle at a rate of the pedals moving 60 rev/min. The length of the pedal arms is 30 cm.

What is the power delivered to the bicycle by the athlete?

a) 15 W
b) 30 W
c) 45 W
d) 60 W

Answer 1

To calculate the power delivered to the bicycle by the athlete, you can use the formula Power = Force x Distance / Time. Substituting the given values, the power delivered is approximately 0.472 W.

Step-by-step explanation:

To calculate the power delivered to the bicycle by the athlete, we need to use the formula:
Power = Force x Distance / Time

The force applied by the athlete is 50 N. The distance traveled by the pedals in one minute can be calculated using the formula:
Distance = Circumference x Number of Revolutions

The circumference of the circle formed by the pedal arms is 2 x π x 0.3 m. The number of revolutions in one minute is 60. Substituting these values into the formula for distance, we find that the distance is approximately 0.565 m/min. Finally, to calculate the power, we can substitute the values into the power formula:
Power = 50 N x 0.565 m/min / 60 s

Simplifying the expression gives us a power of approximately 0.472 W. Therefore, the power delivered to the bicycle by the athlete is approximately 0.472 W.