Torque

Torque is the name physicists give to that which causes objects to rotate; a sort of twisting force.
There are several different ways to calculate the torque created by a force applied some distance from a pivot point, but they all boil down to
```
      torque  =  (distance from pivot) * (force) * sin(theta)
```
where theta is the angle between radius from pivot to force, and the direction of the force.
Strictly speaking, torque is a vector quantity, which is always perpendicular to both radius and force; but for now, we'll describe torques by the direction they tend to rotate the object in question: clockwise or counter-clockwise.
If a force is applied through the center of mass of an object, the object moves with pure translation; but if the force doesn't point through the center of mass, the object will tend to rotate.

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