(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Consider the example of a positive charge q moving in the xy plane with velocity [tex]\hat{v}[/tex] = vcos([tex]\theta[/tex])[tex]\hat{x}[/tex] + vsin([tex]\theta[/tex])[tex]\hat{y}[/tex] (i.e., with magnitude v at angle [tex]\theta[/tex] with respect to the x-axis). If the local magnetic field is in the +z direction, what is the direction of the magnetic force acting on the particle?

Express the direction of the force in terms of [tex]\theta[/tex], as a linear combination of unit vectors, [tex]\hat{x}[/tex], [tex]\hat{y}[/tex], [tex]\hat{z}[/tex].

2. Relevant equations

Cross product.

[tex]\vec{C}[/tex] = [tex]\vec{A}[/tex] X [tex]\vec{B}[/tex] = (A_{x}B_{y}- A_{y}B_{x})[tex]\hat{z}[/tex] + (A_{y}B_{z}- A_{z}B_{y})[tex]\hat{x}[/tex] + (A_{z}B_{x}- A_{x}B_{z})[tex]\hat{y}[/tex]

3. The attempt at a solution

I don't know what to plug in, and overall am just confused as to what the formula means.

Any explanation would be greatly appreciated!

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# Homework Help: Force on Moving Charges in a Magnetic Field

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