Given two vectors find a unit vector that is perpendicular

AI Thread Summary
To find a unit vector perpendicular to the given vectors A and B, first calculate the cross product, resulting in the vector (-13, 6, -11). Next, determine the magnitude of this vector, which is the square root of 326. Divide each component of the cross product by this magnitude to obtain the unit vector. The signs of the components can remain the same or be inverted, as both options yield a perpendicular vector. The final unit vector can be expressed in the form N_x, N_y, N_z.
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Given two vectors \vec{A} = - 2.00 \hat{ i } + 3.00 \hat{ j } + 4.00 \hat{k} and \vec{B} = 3.00 \hat{ i } + 1.00 \hat{ j } - 3.00 \hat{k}. Obtain a unit vector perpendicular to these two vectors.

Express your answer as a unit vector N_unit in the form N_x, N_y, N_z where the x, y, and z components are separated by commas.

i know this involves the cross product but I am stuck on what to do, can someone help me please?
 
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Fist calculate the cross product of the two vectors

\vec{A} = - 2.00 \hat{ i } + 3.00 \hat{ j } + 4.00 \hat{k}

and

\vec{B} = 3.00 \hat{ i } + 1.00 \hat{ j } - 3.00 \hat{k}


ehild
 
i get -13, 6, -11, if my calculations are correct. do i need to find the magnitude of this? sqrt of 326... hen divide by this amount for each. Do I also need to change the +/- signs to make it perpendicular
 
Last edited:
The vector product is correct. The magnitude is correct. Yes, divide each component with the magnitude. You can use the signs as they are or change all to opposite, the vector stays perpendicular.

ehild
 
ty so much for your help
 
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