Electrical concepts, clearly explained
From charge and Ohm’s law to protective earthing and EV high-voltage systems. Each concept includes a definition, three levels of explanation, formulas, solved examples, applications, measurement notes, mistakes and safety guidance.
What Is Electricity?
Electricity is the presence and motion of electric charge. Learn what charge is, how current flows in a circuit and how electric...
Electric Charge
Electric charge is the property that makes particles attract or repel and that gives rise to electric fields. Learn its unit, it...
Electric Field
An electric field describes the force a charge would feel at each point in space. Learn field strength, field lines, the inverse...
Electric Potential
Electric potential is potential energy per unit charge at a point. Learn how potential differs from voltage, how it is measured...
Voltage (Potential Difference)
Voltage is the electrical pressure that drives current. Learn what a volt means, how EMF differs from terminal voltage, and how...
Electric Current
Electric current is the rate at which charge flows through a conductor. Learn the ampere, conventional current direction, curren...
Electrical Resistance
Resistance opposes the flow of current and converts electrical energy into heat. Learn the ohm, resistivity, temperature effects...
Electrical Units and SI Prefixes
Volts, amperes, ohms, watts and their prefixes form the language of electricity. Learn the SI units, derived units and how to co...
Ohm’s Law
Ohm’s law links voltage, current and resistance with V = I × R. Learn the formula triangle, the limits of the law and how to use...
Kirchhoff’s Current Law (KCL)
Kirchhoff’s current law states that the charge entering a node equals the charge leaving it. Learn the node equation, sign conve...
Kirchhoff’s Voltage Law (KVL)
Kirchhoff’s voltage law states that voltages around a closed loop sum to zero. Learn the loop equation, sign conventions and how...
Faraday’s Law of Induction
Faraday’s law says a changing magnetic flux induces an EMF. Learn the formula, Lenz’s sign, motional EMF and how generators and...