While multiplying 2 vectors how do I know if I should use dot product or cross product?

01-Dec-2015 3:04 PM

Answers (1)


It actually depends on the situation you want to use the multiplication. For some applications, dot product is used, while for others cross product is useful.

The dot product gives a scalar number, while a cross product gives us a vector only.

For example, to find the angle between two vectors, you can use cross product easily to find: cos\theta = \bar{A} . \bar{B} / |A||B|

While to find the vector perpendicular to the plane of the 2 vectors, or to calculate torque,it is given by its cross product only.

01-12-2015 17:47

You need to Log in to submit an answer

  • Answer Questions and earn reputation points
  • Related