Faraday's Law Calculator

How We Generate Electricity (The Secret)

Have you ever wondered how a dam, a wind turbine, or a nuclear power plant actually creates electricity? They all rely on the exact same principle discovered by Michael Faraday in 1831.

Faraday's Law of Induction describes how changing a magnetic environment creates electricity. If you take a magnet and move it quickly through a loop of wire, the invisible magnetic field pushes the electrons in the wire, creating a current.

Simply put: Motion + Magnetism = Electricity.

The Equation

• Ɛ (EMF): Electromotive Force. This is essentially Voltage, measured in Volts (V).
• N (Turns): The number of loops of wire. More loops = More voltage.
• ΔΦ (Delta Phi): The change in Magnetic Flux (strength of magnetic field passing through the loop), measured in Webers (Wb).
• Δt (Delta t): The time it takes for the change to happen. Faster movement = Higher voltage.

What is the "Negative" Sign? (Lenz's Law)

You will notice a negative sign at the start of the formula. This represents Lenz's Law, which is nature's way of saying "you don't get something for nothing."

The law states that the direction of the induced current will always oppose the change that created it.

Real World Applications

Faraday's law isn't just textbook theory; it powers modern civilization.

1. Induction Cooktops

Instead of using a flame, these stoves use coils of copper wire under the glass. Alternating current flows through the coil, creating a rapidly changing magnetic field. This field induces currents (Eddy Currents) directly inside your steel pan, heating the pan instantly without the stove itself getting hot.

2. Wireless Charging (Phones)

Your wireless charger contains a coil. Your phone contains a receiving coil. The charger creates a fluctuating magnetic field, which jumps the air gap and induces a voltage in your phone's coil, charging the battery.

3. Electric Guitars

The "Pickup" on a guitar is just a coil of wire wrapped around a magnet. When the steel guitar string vibrates nearby, it changes the magnetic field. This change induces a tiny voltage in the coil, which travels to the amp to become sound.

Motor vs. Generator

Faraday's Law helps explain the difference between these two machines. They are physically identical but work in reverse.