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Torque and the 14,000 machine
Your first question will probably be 'what is torque?', and your second will be 'what is that weird machine on the left?'

The answer to the second is easy, the first is not. That machine is a weird piece of kit that can reduce the speed of a motor wheel 13,824 times with just six cogs. What it does is to use a worm gear three times over, and this is explained in detail below.

The answer to the first question is a lot harder. When you speed up a gear (see Standard Gears for more information) you can increase the rotation for what seems to be nothing. But in life, there is no such thing as a free lunch. A rotating axle has speed and torque. The speed is how fast it is spinning and the torque is about how much force a rotating axle is capable of suppling. The more torque, the more power the wheel has. Here is an example. When you want to build a crane to lift big weights, do you reduce the gear ratio or increase it. You reduce it (or should do) and this is because as you reduce the speed, the torque or capable power increase.

This may still seem a bit complicated, but here is a more practicle example. If you build a rotating axle and attach it to a cog which increases the ratio, is it easier to stop the standard speed of the motor or the increased speed. The answer is the increased speed because it has less torque

I can imagine that this will still seem very complicated, as it did to me when I first read it all. The bottom line is that increasing speed reduces torque and decreasing speed increases torque. Torque is the resistant and power that a spinning wheel can provide. But what has this to do with that '14,000 machine' or whatever it is. Well this is basically a demonstrator of how torque works. The motor is connected to a worm gear which drives a standard gear which is connected to another worm gear which drives another standard gear which is connected to another worm gear which drives yet another standard gear. Each axle also has a wheel connected to it.

By turning on the motor, you power the worm gear which makes the next standard gear move 24 times as slow. This, connected to the next gear makes the second standard gear move 24 times as slow as that worm gear, or 576 times as slow as the first gear. You can see how the calculations would continue.

Torque comes in when you look at the wheels. You will find it quite easy to resist the first wheel, as it is spinning with a torque level of, lets say, x. However, the second wheel is moving 24 times as slow, which means you must deal with 24x. If you try to stop it you will probably find that the model blows itself apart. In theory, the third wheel should be totally impossible to stop, but 576x is so slow that you will hardly see it moving.

You will find building this model very worthwhile, as it demonstrates torque well and is fun to play with.

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