| Description | He has verified graphically that a change in origin in the original pole track diagram makes no difference to the form of the final torque curve, although it may change orientation, or expand or contract it. He gives the example of a circular track of 428 days with the origin at the centre, and then the consequence of shifting the origin along a line of radius, illustrated by a diagram. Hills outlines what happens when the origin is moved to any other radius, the torque diagram revolving through a corresponding angle. Torque has constant direction so long as the origin lies along a radius, again with a diagram. |