The meaning of torque

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This post was last edited by Black Gold on 2011-11-8 11:25. I didn’t know much about this concept before. Today I saw a better explanation. I hope I can share it with you! ~ What is torque? ? Let’s talk about torque. Torque is not a force, because force cannot express the force on a rotating object. Why can’t it be expressed? ? ? Because any rotating object has different forces at different radii, the closer it is to the center, the greater its force, and the greater the radius away from the center, the smaller the force (this is absolutely correct, and it is a high degree of unity between theory and practice. If you don’t know, that’s because you don’t pay attention at ordinary times). The concept of torque is introduced at this time, which is very timely. Torque represents the product of force and radius. For example, the crankshaft output is 120n * m means that there is a force of 120 Newtons (nearly 12.2kg) at the radius of one meter of the crankshaft. Of course, generally speaking, the radius of the crankshaft flywheel is very small. For example, its radius is only 60mm. Then it has a force of 2000 Newtons at the outermost diameter (a force of about 204kg). The torque output by the engine (its original torque) is not large, and it cannot directly drive the rear wheels to start or accelerate. At this time It is necessary to reduce the rotation speed of the engine to increase the torque. Generally, cars have 5 gears. The first gear can reduce the engine speed by about ten times when it is finally transmitted to the rear wheels. The fifth gear can reduce it by about 3 times, and the torque will be increased by about ten times or 3-4 times (of course, the efficiency of the transmission is consumed, but this efficiency is relatively high, we will not count it here for the sake of explaining the problem),,, Now let me explain why lowering the speed can increase the torque. Here we simplify the example. Assume that the front gear has 20 teeth and the rear gear has 60 teeth. That is, 20 teeth transmit 60 teeth. Then we can know that the contact point radius of the rear gear is 3 times the contact point radius of the front gear. Suppose the torque of the front gear is 200 Nm, and its gear contact point radius is 0.1 meters. Then the force of its contact point is 2000 N. At this time, it completely transmits the 2000 N force to the contact point of the 60-tooth gear. Because we know earlier that the contact point radius of the 60-tooth gear is 0.3 meters, the torque of the large gear at this time is 2000x0.3=600 n * m That’s it, the torque has been increased in this way. If you don’t understand anything, you are welcome to discuss it. It is best to conduct a topic discussion instead of inserting other content, because this will only confuse your own thinking. Only when this concept is completely clear, we can introduce other concepts.