- Magnetic fields are represented with the symbol $\vec{B}$
- Magnetism is based in *electric charge*, specifically the motion of that charge.
- The magnetic force is always at right angles to both the velocity $\vec{v}$, and the magnetic field $\vec{B}$
- The force is greatest when the charge is moving at right angles and is zero for motion parallel to the field. THe force is generally proportional to $\sin(\theta)$, where $\theta$ is the angle between the velocity $\vec{v}$, and the field $\vec{B}$.
The formula that describes magnetic force compactly is:
$$ \vec(F_B) = q\vec(v) \times \vec{B} $$
	- $F_B$ is the magnetic force
	- $q$ is the charge the force is acting on
	- $v$ is the velocity of the charge
	- $B$ is the magnetic field
For the magnitude of a magnetic force:
	$$ |\vec(F_B)| = |q|vB\sin(\theta) $$
For the radius of a particle's circular path:
$$ r = \frac{mv}{qB} $$For the period of a particle's circular orbit in a uniform magnetic field:
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