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    (Original post by B_9710)
    Yes that's what the hat above the n means.
    When you simply find the cross product of 2 non parallel vectors, say a and b your answer gives a vector that is perpendicular to both a and b, but this perpendicular vector does not necessarily have a magnitude of 1.
    So if  \mathbf{\hat{n}} always has a magnitude of 1, why is it included in the cross product formula? Is it so it gives the cross product direction?
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    (Original post by Megan_101)
    So if  \mathbf{\hat{n}} always has a magnitude of 1, why is it included in the cross product formula? Is it so it gives the cross product direction?
    Because when you find the cross product of 2 vectors you get a normal vector and the magnitude of th vector is the product of the magnitude of the two vectors. If the  \mathbf{\hat{n}} was not in the formula then it would say that when you cross multiply two vectors that you get a scalar - which is not true - you get a vector.
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    maybe useful:
    • to prove that two not null vectors are parallel, just prove that their cross product is zero.
    • to prove that two not null vectors are perpendicular, just prove that their dot product is zero.
    interesting:
    Finding the absolute value of the dot product of a vector a with the cross product of two other vectors b and c, we find the volume of a parallelepiped with sides a, b, c.
 
 
 
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