Given two vectors find a unit vector that is perpendicular

Click For 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.
1man
Messages
16
Reaction score
0
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?
 
Physics news on Phys.org
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
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

Similar threads

Replies
26
Views
2K
Replies
2
Views
1K
  • · Replies 3 ·
Replies
3
Views
947
Replies
11
Views
2K
Replies
12
Views
2K
Replies
1
Views
737
  • · Replies 8 ·
Replies
8
Views
3K
Replies
8
Views
1K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 11 ·
Replies
11
Views
3K