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‫Welcome back.

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‫Now that we have covered the DOT product, let's talk about the cross product.

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‫Now, when we talk about cross products, then what you need to know is that the result of a cross product

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‫is a vector and not scalar in this vector is not any kind of vector.

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‫If you cross two vectors, let's say the one vector, cross the two vector, then the resulting vector

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‫is perpendicular to both of these vectors.

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‫For example, if the one and two are both on the x y plane, then the resulting vector would be either

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‫in the positive or negative, the Z direction.

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‫So here's an example.

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‫I have three inertia frames here and you can see that the mesh here is the X Y plane.

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‫So I put the one vector here, I put V to Vector here.

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‫Both of them are on the X Y plane and the resulting vector will be in the Z direction like this in this

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‫vectors perpendicular to this one and to this one.

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‫Or if my V one vector vectors like this in my V two vectors like this, then that would be the resulting

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‫vector in the negative Z direction.

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‫Or if my V one vector is like this and my V two vectors like this, then that would be my result.

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‫Note that the more parallel V one and the two are, the smaller the cross product result is in magnitude

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‫and the more perpendicular they are, the bigger their answer is in magnitude.

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‫Why is it like that?

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‫Well, that is because when you have V one cross the two, then you only take that component of V two

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‫that is perpendicular to V one, and then you multiply V one by this perpendicular component of V to

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‫this component that is perpendicular to V one.

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‫And so you multiply their magnitudes and that's why the more perpendicular the vectors themselves are,

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‫the bigger their product and the more parallel they are, the smaller their product.

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‫If V one and the two are completely parallel, then their cross product would be zero because then V

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‫two wouldn't have any perpendicular component to the vector V one and went V one.

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‫And we two are completely perpendicular.

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‫That you have 90 degrees here.

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‫Well, then their cross product will be the biggest in terms of magnitude.

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‫Now, the direction of the one across the EU is determined by the right hand rule, if you want to know

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‫the direction of the one crossfield to the new first point, your right hand fingers in the direction

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‫of the EU, one like this, and then you turn them in the direction of the two and your thump on your

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‫right hand will give you the direction of the one cross the two.

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‫However, if you want to find V to cross V one, then it is in reverse like this, your right hand fingers

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‫first point in the direction of V to then you turn your fingers in the direction of the one and your

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‫thumb will point down, giving you the direction of V to cross V one.