Torque & Speed Graphs - What Does No Torque Mean?

AI Thread Summary
When a motor reaches its maximum speed with no torque, it indicates that the system is maintaining speed primarily through momentum rather than active force. At low speeds, high torque is necessary to overcome inertia, but as speed increases, less torque is required to counteract drag and friction. The absence of torque at the shaft output does not mean torque is not being produced; rather, it is consumed by internal friction and other losses. This dynamic illustrates the relationship between torque and acceleration, where minimal torque is needed to sustain top speed. Understanding this concept is crucial for analyzing motor performance and efficiency.
Jones1987
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When the motor is producing its top speed, and there is no torque, I cannot picture what this means. I understand that low speeds = high torques, as I can picture an object moving slowly because of its torque.

I undersrtand torque as the force that creates rotation, so if a shaft is rotating at its max speed, and it reads out no torque, why is this? Is this due to the momentum the shaft has therefore it no longer needs torque?
 
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Think of torque like acceleration. One you hit top speed, you need very little acceleration to counteract drag/friction to maintain that top speed.
 
There is no torque at the shaft output, but there is still torque being produced. It is only all taken by internal friction and other losses.
 
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