What is external torque?

1. Apr 8, 2014

Muthumanimaran

is there any difference between external torque and torque?

2. Apr 9, 2014

SunnyBoyNY

Motor control engineer here (so my answer is not really physics-based):

Torque - EM torque developed by an electric machine
External torque - torque imposed by load (positive - generators such as gas/wind, negative - fans, compressors, etc.)

3. Apr 10, 2014

clem

Draw a free body diagram. If the force producing the torque is external to a circle drawn around the body, the the force and its torque are external.