Eli5: Hoe does that experiment with multiple gears that with each one added the first one goes even faster works?
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For a rotation, the power is the rotational speed multiplied by the torque.
Speed is this case is revolution per unit of time. Torque is rotational force and power is energy per unit of time.
So you can transfer the same energy with fast rotation and low torque as with slow rotation and high torque.
When you have a large wheel that drives a small wheel the rotational speed increase, at the same time the torque decrease. If the rotational speed is 10x higher the torque will be 1/10.
Ideally to the same degree so the power is constant but in practice, you always have some losses due to friction.
So no energy conservation laws are broken.
It is not really any different if you go a step and short road up a hill compared to a longer but less steep the same distance. To reach the top at the same time you need to go faster on the longer path, the force you need to keep the speed is lower than if you go up the steep path. In the end, the required energy is ideally identical, it practices friction and other losses could be more on one the other path
Les say you have a setup like that you power by hand and try to keep the last gear rotation at a constant speed. If you add another gear to the system and change to driving it by hand the speed you need to move your hand is decreased. the force you need to apply to keep it going will increase. Because of friction, the power from you has to increase slightly.
In practice, there will be a limit on how many stages you can use because frictional losses increase power requirements and there is a max torque your body can apply.
For a rotation, the power is the rotational speed multiplied by the torque.
Speed is this case is revolution per unit of time. Torque is rotational force and power is energy per unit of time.
So you can transfer the same energy with fast rotation and low torque as with slow rotation and high torque.
When you have a large wheel that drives a small wheel the rotational speed increase, at the same time the torque decrease. If the rotational speed is 10x higher the torque will be 1/10.
Ideally to the same degree so the power is constant but in practice, you always have some losses due to friction.
So no energy conservation laws are broken.
It is not really any different if you go a step and short road up a hill compared to a longer but less steep the same distance. To reach the top at the same time you need to go faster on the longer path, the force you need to keep the speed is lower than if you go up the steep path. In the end, the required energy is ideally identical, it practices friction and other losses could be more on one the other path
Les say you have a setup like that you power by hand and try to keep the last gear rotation at a constant speed. If you add another gear to the system and change to driving it by hand the speed you need to move your hand is decreased. the force you need to apply to keep it going will increase. Because of friction, the power from you has to increase slightly.
In practice, there will be a limit on how many stages you can use because frictional losses increase power requirements and there is a max torque your body can apply.
For a rotation, the power is the rotational speed multiplied by the torque.
Speed is this case is revolution per unit of time. Torque is rotational force and power is energy per unit of time.
So you can transfer the same energy with fast rotation and low torque as with slow rotation and high torque.
When you have a large wheel that drives a small wheel the rotational speed increase, at the same time the torque decrease. If the rotational speed is 10x higher the torque will be 1/10.
Ideally to the same degree so the power is constant but in practice, you always have some losses due to friction.
So no energy conservation laws are broken.
It is not really any different if you go a step and short road up a hill compared to a longer but less steep the same distance. To reach the top at the same time you need to go faster on the longer path, the force you need to keep the speed is lower than if you go up the steep path. In the end, the required energy is ideally identical, it practices friction and other losses could be more on one the other path
Les say you have a setup like that you power by hand and try to keep the last gear rotation at a constant speed. If you add another gear to the system and change to driving it by hand the speed you need to move your hand is decreased. the force you need to apply to keep it going will increase. Because of friction, the power from you has to increase slightly.
In practice, there will be a limit on how many stages you can use because frictional losses increase power requirements and there is a max torque your body can apply.
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