Electrical Systems Last Chance Checklist

AS91526 NCEA Level 3 2026

Define Electromotive Force

The energy converted to electrical energy per unit of charge

Calculate the Electromotive Force

ε = V + Ir

Kirchhoff’’s Current Law

The total current entering a junction is equal to the total current leaving the junction

Kirchhoff’s Voltage Law

Around a complete loop, the sum of the electromotive forces is equal to the sum of all potential differences

(Basically, the sum of the voltages around a closed loop in a circuit is zero)

What is a Capacitor?

An electrical component that STORES electrical charge

What is the basic structure of a Capacitor?

A capacitor consists of two parallel metal plates that are separated by an insulator

Symbols & Units for Capacitance (or capacitance permittivity)

Symbol: C Units: Farads (F)

Symbols & Units for Relative Permittivity

Symbol: ε_R or k Units: None

Symbols & Units for Dielectric Permittivity

Symbol: ε Units: Farads per meter (Fm^-1)

Vacuum Permittivity Constant

ε₀ = 8.85×10^-12 Fm^-1