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IMK
Dec6-07, 06:54 AM
Hello,
In attached image the three black lines represent three force vectors x,y,z of some arbitrary magnitude, these I can normalize and by taking the sin-1 I get there effect angle. What I would like to calculate is the angle between any two of the black line axies thus theta xy = ?. also I would like to calculate the angle between any of the x,y,z axies and the and the central red vector.

Many thanks in advance IMK

HallsofIvy
Dec6-07, 07:13 AM
In order to "calculate" the angle (as opposed to measuring it) you have to be "given" the vectors in some "calculable" form. How you would then calculate the angle depends on how you are given the vectors. How are you given x, y, and z, other than just a drawing?

IMK
Dec6-07, 09:25 AM
In order to "calculate" the angle (as opposed to measuring it) you have to be "given" the vectors in some "calculable" form. How you would then calculate the angle depends on how you are given the vectors. How are you given x, y, and z, other than just a drawing?

These would be force vectors that I would normalize to be in the range of 0 to 1
Many thanks in advance IMK

nicksauce
Dec6-07, 09:36 AM
\vec{A}\cdot\vec{B}= \|\vec{A}\|\|\vec{B}\|\cos{\theta} and
\|\vec{A}\times\vec{B}\|=\|\vec{A}\|\vec{B}\|\sin{ \theta}. You can use either of these to calculate the angle.

IMK
Dec6-07, 12:13 PM
\vec{A}\cdot\vec{B}= \|\vec{A}\|\|\vec{B}\|\cos{\theta} and
\|\vec{A}\times\vec{B}\|=\|\vec{A}\|\vec{B}\|\sin{ \theta}. You can use either of these to calculate the angle.
Many thanks!