Electricity & Magnetism
Every electricity & magnetism calculator on CalcEngines — each with its formula, a worked example, the standard it follows and the assumptions it makes.
8 calculators in this section
- Coulomb’s Law and Electric Field of a Point Charge CalculatorGive me two charges and how far apart they are, and this returns the force on each of them, the field each one makes where the other sits, the signed answer that separates attraction from repulsion, the pair's potential energy, and the separation that would make the force exactly one newton.
- Drift Velocity and Current Density CalculatorThe number that surprises everyone: switch on a lamp and the electrons in the wire crawl at a fraction of a millimetre a second, while the lamp lights at once. This works out the drift speed from the current and the wire — and works out n, the free electron density, from the metal's density rather than asking you to look it up.
- Electric Potential and Potential Energy CalculatorPotential is a scalar, so you ADD the contributions instead of resolving them — which is what makes it easier than the field. Two charges, one point, and this returns the net potential there, the energy of a test charge brought in from infinity, the work each party does, and the same energy in electronvolts.
- EMF, Internal Resistance and Terminal Voltage CalculatorA cell's emf is what its chemistry supplies; its terminal voltage is what the outside world gets. This returns both, the lost volts in between, the share of the power that never leaves the battery, the short-circuit current, and the load that would draw the most power — for any number of identical cells in series and in parallel.
- Magnetic Field of a Wire, a Coil and a Solenoid CalculatorThe three geometries every syllabus asks for, in one place, with the Earth's own field printed beside the answer as a yardstick — and a note on why μ₀ is no longer exactly 4π × 10⁻⁷ and why the ampere is no longer defined by the force between two wires.
- Magnetic Force on a Moving Charge and a Current CalculatorF = qvB sin θ and F = BIL sin θ are the same equation twice, because qv and IL have the same units. This returns both, the radius and period of the circular path a charge would follow, and the one number that is always exactly zero — the work a magnetic force does.
- Metre Bridge Calculator: Unknown Resistance from Balance LengthGive me the known resistance and where the galvanometer went quiet on the wire, and this returns the unknown resistance, the uncertainty the balance point itself carries, and the known resistance you should have chosen instead — because the fractional error is worst at the ends of the wire and smallest at 50 cm.
- Parallel Plate Capacitor and Dielectric CalculatorCapacitance from the geometry, and then the question every exam asks: was the battery still connected when the dielectric went in? Leave it connected and the charge rises; disconnect it first and the voltage falls instead. This page makes you choose, and shows what each choice does to Q, V, E and the stored energy.