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Is there any torque caused by uniform force fields?

The torque caused by superposition of uniform force fields acting on a rigid body can be expressed as:

(1)

The ~ tilde character above a 3D point/vector denotes object space. The center of mass of a rigid body is expressed as:

We define object space of a rigid body to have its origin right at its center of mass. So, by using the tilde notation we can derive the following implication:

(2)

By plugging (2) into (1) we get:

References:

[1] Feynman, R. P., Feynman Lectures on Physics (3 Volume Set), Volume 1, Czech Edition

[2] Baraff, D., An Introduction to Physically Based Modeling: Rigid Body Simulation I - Unconstrained Rigid Body Dynamics