Formulas for electricity.

Force on a moving charge in a magnetic field

  • Given by:
\begin{align} F = qvb\sin{\theta} \end{align}
  • Note that $\theta$ is the angle between the particle's direction of movement and the magnetic field lines.
  • Direction of the force is given by the Right hand palm rule, where I is given by the direction of the particle
    • Note that, if it is an electron, the thumb points in the opposite direction.
  • Be aware of the following:

Electric fields

  • Electric field strength is given by
\begin{align} E_f =\frac{V}{d} \end{align}
  • Note that it is the same between the metal plates, no matter the position in between them.
  • Do not get this confused with Energy, which is why it's written as $E_f$ here instead.
  • The force on a charged particle in this field is given by:
\begin{equation} F = q E_f \end{equation}
  • Note that the direction of this force is given by the charge of the particle.
    • A negative charge would move towards the positive and away from the negative.
    • A positive charge would move towards the negative and away from the positive.