What then is in unit-vector notation if Bx = By?

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To solve for the magnetic field components Bx, By, and Bz in the equation F = qv x B, given that Bx = By, one must first set up the cross product correctly. The equation simplifies to a determinant involving the unit vectors i, j, and k, leading to a system of equations based on the components of the force F. By substituting Bx for By, the equations can be solved simultaneously to find the values of Bx and Bz. The user is seeking guidance on the next steps to isolate and solve for these variables. The discussion emphasizes understanding the cross product and matrix determinants in vector calculations.
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Homework Statement



In the product F = qv x B , take q = 4,
v = 2.0i + 4.0j + 6.0k and F= 136i -176j + 72k.
What then is in unit-vector notation if Bx = By?

Homework Equations



136i-176j+72k = 8i+16j+24k + Bxi+Byj+Bzk

The Attempt at a Solution



I am stuck with the above equation. How do I solve for Bxi, Byj and Bzk?
 
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You're not adding the B-components, you're taking the cross product. Recall the 3x3 matrix with i, j, and k in r1. You have to find the determinant of that matrix to solve for F, which is given to you.
 
oops I did a typo. I know that. It's:
136i-176j+72k=8i+16j+24k X Bxi+Byj+Bzk
So If I find the determinant from the right hand side it's:
136i-176j+72k=((16)(Bz)-(By)(24))i+((24)(Bx)-(Bz)(8))j+((8)(By)-(16)(Bx))k
136i-176j+72k=(16Bz-24By)i+(24Bx-8Bz)j+(8By-16Bx)k

Now what do I do?
 
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?

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