- The vector or cross product is another way to combine two vectors; it creates a vector perpendicular to both it the originals.
- In vector form, torque is the cross product of the radius vector (from axis of rotation to point of application of force) and the force vector.

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There are other ways of computing and expressing the
cross product of two vectors.
For example, given two vectors **A** and **B**
in the standard
unit-vector notation

one can combine the components of the two vectors to form
the cross product **A x B** like so:

One way to remember this particular arrangement is to
consider the cross product as a **determinant**
(see Appendix E of your physics text):

We are interested in one particular cross product:

Note several things:

- the maximum size of the torque is the
product of the magnitude of
**r**and the magnitude of**F** - the direction of the torque will be perpendicular
to both
**r**and**F** - if a force points straight toward (or away from) the axis of rotation, then the torque due to that force is zero