Lectures on Physics has been derived from Benjamin Crowell's Light and Matter series of free introductory textbooks on physics. See the editorial for more information....

How torque depends on the direction of the force

How can the torque applied to the wrench in the figure be expressed in terms of r , |F|, and the angle θ?

The force vector and its F? component form the hypotenuse and one leg of a right triangle,

and the interior angle opposite to F equals θ. The absolute value of F can thus be expressed as

F = |F| sin θ ,

leading to

|τ| = r |F| sin θ .

The quantity r

Last Update: 2010-11-11