Controls
Experiment Readout
Voltage: 7
Spark gap: 0.55 m
EM wave: ready
Receiver spark: waiting
This interactive 3D physics simulation demonstrates the famous Hertz experiment. Heinrich Hertz used a spark gap transmitter and a receiver loop to confirm Maxwell’s prediction that electromagnetic waves exist and can travel through space.
1. Induction coil: produces a high voltage across the spark gap.
2. Spark gap transmitter: creates a rapidly changing current when a spark jumps between two metal spheres.
3. Electromagnetic waves: spread outward from the transmitter through space.
4. Resonator receiver loop: detects the electromagnetic wave by producing a small spark across its gap.
Maxwell’s theory predicted that changing electric fields and changing magnetic fields support each other and travel as electromagnetic waves. Hertz confirmed this idea experimentally. In this simulation, the spark gap acts as a transmitter. The receiver loop acts as a detector. When the wave reaches the loop, it induces an electric current, and a small spark appears at the receiver gap.
Hertz’s experiment provided direct evidence that electromagnetic waves are real. This discovery became the foundation for radio, television, radar, Wi-Fi, Bluetooth, cell phones, and modern wireless communication.
In the real Hertz experiment, electromagnetic waves are invisible and spread outward through space. In this simulation, the waves are drawn as horizontal expanding wavefronts so students can clearly visualize wave propagation from the spark-gap transmitter to the receiver loop.