Capacitance

What is a parallel plate capacitor composed of?

Two equal metal plates placed parallel to each other.

What acts as the dielectric medium in a simple parallel plate capacitor?

Vacuum or air.

How is capacitance defined?

Capacitance (C) is the ratio of charge (Q) on one plate to voltage (V) across the plates: C = Q / V.

What is the unit of capacitance?

Farad (F), where 1 F = 1 coulomb per volt (C/V).

What is the formula for capacitance of a parallel plate capacitor without a dielectric?

C = ϵ₀ A / d, where ϵ₀ is the permittivity of free space.

How does a dielectric material affect the capacitance of a capacitor?

It increases capacitance, allowing the capacitor to store more charge for the same applied voltage.

What is the expression for capacitance with a dielectric?

C = κ ⋅ ϵ₀ A / d.

What is the formula for the electric field (E) in a parallel plate capacitor?

E = V / d, where V is the potential difference and d is the distance between plates.

What is the formula for energy (U) stored in a capacitor?

U = ½ QV.

What is the formula for total capacitance of capacitors in series?

1 / C_total = 1 / C₁ + 1 / C₂ + ⋯

How is total capacitance of capacitors in parallel calculated?

C_total = C₁ + C₂ + ⋯

What occurs during the charging of a capacitor through a resistor in an RC circuit?

The voltage across the capacitor increases while the current decreases over time.

What is the formula for the charge on a capacitor while charging?

Q(t) = Q₀ (1 − e^(-t / RC)).

What is the discharging equation for a capacitor?

Q(t) = Q₀ e^(-t / RC).