andykol
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Calculating surface normal vector
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Welcome to PF!
Hello andykol! Welcome to PF!
I'm not sure what you're asking
…
you don't need the normal vector …
to calculate the normal component for U, all you need is the angle, θ, between Nf and U …
the normal component of U is simply Ucosθ.
Hello andykol! Welcome to PF!
andykol said:
I'm not sure what you're asking
…you don't need the normal vector …
to calculate the normal component for U, all you need is the angle, θ, between Nf and U …
the normal component of U is simply Ucosθ.
slider142
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More information is necessary. In any coordinate system, a vector normal to another vector has a dot product of 0 with that vector. In 2 dimensions, this simplifies to the normal vector having the negative reciprocal slope of the vector it is normal to. you haven't given two-dimensional coordinates to the points, nor angles, so there is no way to calculate an absolute normal vector, but if the problem does not relate to any particular coordinate system (ie., there is no potential field; gravity, electromagnetism) then choose a convenient set of coordinates; ie., let that rectangle be horizontal with vertical sides; then the normal vector points along the positive x-axis. You still need the angle between F and N.
andykol
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Thank you for reply.
But I need to calculate unit normal vector for surface F. I am looking for formula that calculates normal vector of surface with any given angle.
But I need to calculate unit normal vector for surface F. I am looking for formula that calculates normal vector of surface with any given angle.
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andykol said:
Sorry, I still don't understand
…how is F defined?
do you have a particular example in mind?
andykol
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