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Vector question

What is the difference between r.n = D and r.ñ = D / | n|?
I'm referring to equation of a plane. Thanks!
Original post by HarryStalks
What is the difference between r.n = D and r.ñ = D / | n|?
I'm referring to equation of a plane. Thanks!


No difference overall. To get from the first eqn to the second all youre doing is dividing both sides by |n|.

The only noticable difference is choosing the unit normal vector in the second case and not necessarily a unit vector in the first case.

As long as your direction of the normal vector is correct, the length doesnt matter so much.
(edited 4 years ago)
Original post by RDKGames
No difference overall. To get from the first eqn to the second all youre doing is dividing both sides by |n|.

The only noticable difference is choosing the unit normal vector in the second case and not necessarily a unit vector in the first case.

As long as your direction of the normal vector is correct, the length doesnt matter so much.

Agreed, and will just add that the second form of the equation r.ñ = D / | n| can be quite useful in that D / | n| is the perpendicular distance from the origin to the plane.
Reply 3
Original post by RDKGames
No difference overall. To get from the first eqn to the second all youre doing is dividing both sides by |n|.

The only noticable difference is choosing the unit normal vector in the second case and not necessarily a unit vector in the first case.

As long as your direction of the normal vector is correct, the length doesnt matter so much.

wew! thanks :smile:
Reply 4
Original post by old_engineer
Agreed, and will just add that the second form of the equation r.ñ = D / | n| can be quite useful in that D / | n| is the perpendicular distance from the origin to the plane.

cool! thank you!

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