T/N and N/T characteristics

When choosing a motor, the manufacturer and user often discuss the characteristics (nature), and the most important and fundamental characteristic at that time is the relationship between torque and rotational speed.
When this is represented in a graph:
◇ If the vertical axis is torque and the horizontal axis is speed, it is called the T/N characteristic.
◇ If the vertical axis is the speed and the horizontal axis is the torque, it is called the N/T characteristic.
In many cases, output and efficiency are also shown superimposed on these graphs. The figure below shows an example showing two representations of the characteristics of the same DC motor.