Induced Currents and Forces Concept

Demonstrations in Induced Currents and Forces

Wooden frame with two vertical rods suspended from springs at the top crossbar, each passing through a copper-wound solenoid coil at the base, yellow position markers on the rods, and a polarity-reversal switch board mounted between the coils

Electromagnetically Coupled Harmonic Oscillators

Demonstrates electromagnetic coupling between two spring-mass oscillators via Faraday induction. Students observe energy transfer through induced currents, phase relationships that depend on coil wiring sense, and rapid electromagnetic damping when …
Hand holding a flexible coil between the poles of a large C-shaped permanent magnet on a wooden base, connected via BNC cable to an Agilent oscilloscope displaying induced voltage pulses

Flexible Coil and Magnet

A flexible coil between magnet poles produces voltage pulses visible on an oscilloscope through three methods: waving (translation), rotating, and compressing/extending the coil. Students see that any change in magnetic …
Overhead projection showing galvanometer face (2 mA DC, scale -2 to +2) with silhouettes of three coils visible to the right

Overhead Galvanometer with Coils

Three coils with different turn counts (30, 50, 90) are connected in series to an overhead galvanometer. Moving a bar magnet through each coil shows that induced EMF scales with, …
Transparent cylindrical Faraday flashlight showing a cylindrical magnet inside a tube with a coil and LED assembly at the lens end with blue ring

Faraday Flashlight

Shaking a magnet through a coil generates current that charges a capacitor and powers an LED — a hands-on demonstration of Faraday's law. Students see the complete energy conversion chain …
Copper wire induction coil on wooden base with banana jacks, clamped vertically on a stand with eggshell foam underneath, connected by leads to a breadboard with two LEDs
Safety

Coil, Magnet, and LEDs

Demonstrates Faraday's law by dropping a magnet through a coil connected to two oppositely-oriented LEDs. Students see that increasing and decreasing flux produce currents in opposite directions, and that reversing …
Overhead galvanometer with clear acrylic faceplate showing ±2 mA DC scale, telegraph key switch, C battery with red leads, and coil set with green primary winding and three red secondary pickup coils on a metal frame
Safety

Electromagnetic Induction

A battery-powered electromagnet core inserted into pickup coils produces galvanometer deflection only during switching transients — demonstrating that induced EMF requires changing magnetic flux (Faraday's Law). Reversing the battery leads …
Agilent oscilloscope displaying induced voltage pulses, with a flip coil held by hand near a C-shaped magnetron magnet on a wooden base
Safety

Flip Coils

A coil inserted into a strong magnet and flipped 180° produces a voltage pulse on an oscilloscope. Students observe that the pulse height depends on flip speed while the integrated …
Complete setup: Xantrex DC power supply set to 3V, knife switch on stand, demountable transformer core with red and black banana cables wound around opposite legs on a wooden base, and a white breadboard with red and green LEDs

Faraday's Induction Experiment

Demonstrates Faraday's Law using a demountable transformer core with hand-wound coils. Closing a switch on the primary circuit causes one LED to flash in the secondary; opening it flashes the …
Agilent oscilloscope on green table showing flat baseline signal, with bundled wire loop coiled on adjacent surface

Earth's Magnetic Field

Demonstrates Faraday's law by detecting the EMF induced when a large wire loop is rotated like a jump rope through Earth's magnetic field (~50 μT). Students see that even a …