[[Electric Force, Field, and Potential]]
# Summary
* Measured in capacitance ($C=\frac{Q}{\Delta V}$), value fixed by physical build $C=\kappa \epsilon_0\frac{A}{d}$
* Field between plates is uniform except near edges. $E_C=\frac{Q}{\kappa \epsilon_0 A}$ (equal to $\frac{\Delta V}{d}$)
* Charged particle between plates feels constant force. Projectile with constant accel.
* Stored energy written as: $U_C=\frac{1}{2}Q\Delta V=\frac{1}{2}C(\Delta V)^2=\frac{Q^2}{2C}$.
* Adding dielectric raises capacitance by factor of $\kappa$, sets up induced field inside dielectric that opposes plate field.
* On AP exam, only parallel plate capacitors required, edge effects ignored unless stated otherwise.