Faraday’s Law Calculator

Written by Great Medico

Updated September 25, 2026 •2 min read

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A faraday’s law result can look convincing even when one unit or assumption is off. Electrical and magnetic results can shift sharply with geometry, frequency, phase, material properties, and whether the quantity is a magnitude or signed value. This page keeps the calculation narrow enough to trace the answer back to the values you enter.

What this calculator does

The Faraday’s Law Calculator connects Coil cross-sectional area, Number of turns in the coil, Magnetic field to the page’s induced voltage. Supporting values are included only when they follow from the same relationship, so you can compare the headline with the quantities behind it.

How to use it

Enter Coil cross-sectional area, Number of turns in the coil, Magnetic field, Time using the units shown beside each field. Keep all values from the same physical case, then check the headline result and any supporting values before changing one input at a time for comparison.

How the calculation works

The current simplified induction path forms magnetic flux per turn Φ = BA and average induced-voltage magnitude ε = NΦ/Δt. It assumes the flux changes from zero to BA over the entered time rather than accepting two independent flux states.

Example

With the default setup (Coil cross-sectional area = 0.01 m²; Number of turns in the coil = 100; Magnetic field = 0.5 T; Time = 0.1 s), the page reports induced voltage of 5 V. This is a useful baseline: change one input and confirm the new value follows the proportionality in the formula.

How to interpret the result

Read the induced voltage with its sign, magnitude, phase, frequency, geometry, and unit as applicable. A field, reactance, power factor, loss, or flux value should be compared only with a quantity defined in the same way.

Limitations and notes

The page uses ε = NBA/Δt as if magnetic flux changes from zero to BA over the entered interval. It does not accept initial and final field values, field angle, or an arbitrary time-varying waveform, so it is an average-magnitude estimate rather than a general Faraday-law solver.