Exploring Work and Power Output Differences in Cyclists on the Same Hill

In summary, the conversation discusses the differences in work and power output between two bicyclists who are cycling to the top of the same hill, with one using a gear that is twice as difficult as the other. The constraint that both cyclists reach the top simultaneously is added, and it is concluded that with this constraint, both cyclists would exert the same power and output the same work over the same time. The difference in force and number of repetitions between the two cyclists is also mentioned, and it is suggested that the difference in bio-physics of the cyclists themselves may play a role.
  • #1
40nni
2
0

Homework Statement



If 2 bicyclists are cycling to the top of the same hill, and one bicyclist is using a gear that is twice as difficult as the other, is there a difference in work and power output between the 2 cyclists?
 
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  • #2
40nni said:

Homework Statement



If 2 bicyclists are cycling to the top of the same hill, and one bicyclist is using a gear that is twice as difficult as the other, is there a difference in work and power output between the 2 cyclists?


Welcome to PF.

What are your thoughts? Which of bicyclists would you bet on?
 
  • #3
LowlyPion said:
Which of bicyclists would you bet on?

The fitter cyclist, every time!

I forgot an important constraint to my question - that both cyclists reach the top simultaneously.

Given that constraint, I'd guess both exert the same power (both output the same work over the same time).

Where I get hung up though, is that the cyclist who is mashing the pedals would be exerting more force over the same distance compared to the cyclist who is spinning faster. I suppose the force by the spinner is greater than I perceive given the greater number of repetitions.

Anecdotally, mashing on a high geared singlespeed is tougher, but I suppose it's all how you train you legs.
 
  • #4
40nni said:
I forgot an important constraint to my question - that both cyclists reach the top simultaneously.

Given that constraint, I'd guess both exert the same power (both output the same work over the same time).

Where I get hung up though, is that the cyclist who is mashing the pedals would be exerting more force over the same distance compared to the cyclist who is spinning faster. I suppose the force by the spinner is greater than I perceive given the greater number of repetitions.

Anecdotally, mashing on a high geared singlespeed is tougher, but I suppose it's all how you train you legs.

You've answered your own question then, at least as far as your constraint. If everything else is equal, like their weight, the net work they both must do is given by m*g*h. If you constrain them to arrive at the same time, then you have constrained them to go at the same speed. The wheels of each must revolve at the same speed with your constraint.

The lower gear will make fewer revolutions of the pedal, but the cyclist must push more forcefully, then to achieve the same progress on the road.

If there is a difference then maybe it's in the bio-physics of the cyclists themselves? One cyclist will have twice the repetitions with his legs to go the same distance over and above the power he delivers to the bike moving forward.
 

FAQ: Exploring Work and Power Output Differences in Cyclists on the Same Hill

What is bicycle work?

Bicycle work refers to the amount of energy required to move a bicycle forward. It is a measure of the effort needed to overcome resistance and propel the bicycle forward.

How is bicycle work calculated?

Bicycle work is calculated by multiplying the force applied to the pedals by the distance traveled. This is known as the work-energy principle, where work is equal to force multiplied by distance.

What factors affect bicycle work?

The main factors that affect bicycle work include the weight of the rider and the bicycle, the terrain (such as hills or flat roads), wind resistance, and the gear ratio of the bicycle.

How can I improve my bicycle work?

To improve your bicycle work, you can try reducing the weight of your bicycle and using lighter gear ratios. You can also improve your cycling technique and increase your fitness level through training.

What is the relationship between bicycle work and speed?

The amount of bicycle work required is directly related to the speed at which the bicycle is traveling. As speed increases, more work is required to overcome air resistance and maintain the speed. This is why it becomes harder to pedal at higher speeds.

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