Module 1 : A Crash Course in Vectors
Lecture 1 : Scalar And Vector Fields
Vector Product (The Cross Product)
  The cross product of two vectors $\vec A\times\vec B $ is a vector whose magnitude is $\mid A\mid\mid B\mid \sin\theta$, where $\theta$ is the angle between the two vectors. The direction of the product vector is perpendicular to both $\vec A$ and $\vec B$. This, however, does not uniquely determine $\vec A\times\vec B $ as there are two opposite directions which are so perpendicular. The direction of $\vec A\times\vec B $ is fixed by a convention, called the Right Hand Rule.
 
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