Explain with the help of a diagram, Hertz experiment for the production of electromagnetic waves.

Explanation

Hertz experiment was based on the fact that em waves are radiated by a vibrating electric charge. Experimental arrangement used by Hertz consists of two large metallic plates P and Q connected to an induction coil. Two metal spheres `S_(1)` and `S_(2)` are connected to these plates P and Q and there is a small air gap between these speheres. the matallic plates behave as a capacitor of capacitance C.

The Wires connecting spheres `S_(1)` and `S_(2)` to the plates provide a low inductance L. The elecromegnetic waves generated in the gap between `S_(1)` and `S_(2)` are detected with the help of a receiver consisting of a circular ring and two spheres `S_(1)^(.)` and `S_(2)^(.)`.
The induction coil procides a very high potential difference across the plates `P_(1)` and `Q_(2)` which in turn ionises the air in the gap between `S_(1)` and `S_(2)`. Due to ionisation of air, a spark is produced in the gap. Oscillations are produced due to this spark, which in turn produces the em waves. The frequency of oscillation is given by
`v=(1)/(2pisqrt(LC))`
Hertz successfully produced em waves of wavelength about 6 m.