Why do larger gear ratios produce greater torque? All that seems to be happening is every subsequent gear is slower than the driver.
In: Physics
Instead of gears look at a block and tackle. If you connect rope trough a single block to pull something you have to pull with half the force but twice as long compared to just a rope. If you have two loops so the rope passes 4 times to the load you have to pull four times the distance but with a quarter of the force. So you trade force for distance.
I physical work=force*distance so you do the same work in all cases.
Torque is a rotational force so the gears work like a block and tackle system. So if you have gears that produce twice the torque the input gear has to rotate twice the number of revolution for the same work. It is the same work=force*distance but for rotation.
Imagine trying to open a door. If you push near the hinge, then the door is quite hard to open but if it is light then it flies open without you moving your hands much. This is akin to a high gear – the engine doesn’t have to move very far to move the car far but it has to push much harder. Pushing far from the hinge makes the door open more easily but it doesn’t go any faster than your hands do. This is a low gear. The engine doesn’t have to push as hard to get a lot of force at the wheels, but they don’t really move any faster than it does.
The same work is relayed over a smaller distance (for a reduction arrangement). Smaller distance means higher force to preserve the amount of work (ignoring friction and all that).
That’s the difference. Imagine your legs were a foot long. You could hike straight uphill, but you’d never get anywhere fast. If your legs were six feet long you could cover large distances quickly, but a slight incline would be exhausting.
You said it the gear gets slower, and As the gear slows down it is still carrying the same amount of energy. That energy come out in the form of being able to push harder.
The reason that it pushes so hard was very studiously stated in the comments above.
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