The Cross Product & Torque (Class 11 Physics)

In physics we say that you apply torque to a nut or you are applying a turning force. The magnitude of the torque is given as the cross product of r and F. Where r is the radial distance of the force F from the center of the nut. The radial distance is treated as a vector pointing outward from the center of the nut which is the origin.

So you could say the physical vector quantity that makes the nut turn is called torque, denoted by the symbol tao. More the value of F or more the value of r, more the turning force or torque

Now what is not so obvious is that the direction of torque is perpendicular to both the vectors r and F. The direction of torque can be found using the right hand rule and we can see that it points in the upward direction here.

[chiefchili]

Oh, and thats why the nut is attached perpendicular to the wrench.

[bushranoor]

Sir please tell me that why cross product of torque is not anticommutative