We built a gearbox for our 3-pole DC motor and then measured torque as a function of speed. This video explains how torque can be measured with a simple setup, and shows how torque and speed in a motor are related to one another.

Aaron Danner is a professor in the Department of Electrical and Computer Engineering at the National University of Singapore.
https://www.ece.nus.edu.sg/stfpage/el...

Video filmed and edited by Cheryl Lim.
@randomcheryl