Vector Cross Product: Perpendicular Vectors lV_1 x V_2l

[horsegirl09]

If vectors V_1 and V_2 are perpendicular, lV_1 x V_2l =? I know that if they are parallel for vector cross product, they equal 0.

 

[mathman]

If vectors V_1 and V_2 are perpendicular, lV_1 x V_2l =? I know that if they are parallel for vector cross product, they equal 0.

The cross product is a vector perpendicular to V_1 and V_2. Also V_1 and V_2 don't have to be perpendicular to each other, only not parallel.

Note that this only makes sense in 3 dimensional space.

Further note: the magnitude is |V_1|x|V_2|cos(a), where a is the angle between the vectors. There is a sign ambiguity.

 

[ehj]

Isn't it |V_1|*|V_2|*sin(a)?

 

[mathman]

Isn't it |V_1|*|V_2|*sin(a)?

You're right - my bad.