Name: Nature of Electromagnetic Waves
Uploaded: 2019-07-19
Duration: 5 min 57 s
Description: Have you ever wondered why light doesn’t push you, the way wind or water do? Or does it? Watch this video to learn how light exerts a force on us.

Question

Draw a labeled diagram of Hertz's experimental set up to produce e.m waves. Explain the generation of electromagnetic waves using this setup.

Accepted Answer

Hertz's experimental setup consists of two metal plates S₁and S₂ parallel to each other at $60 cm$ apart and joined with two spheres S₁and S₂ at $2 - 3 cm$ distance. A rf generator supplying very high voltage. Thus a spark was generated between the two spheres and e.m waves so produces were detected by rf detector ar S^'₁and S₂ ^'

Due to the high potential difference between the spheres, the gas between them is ionised and provides a path for discharge of the plates. Due to it a spark is produced between the spheres and electromagnetic waves of high frequency are radiated. Here the two plates act as a capacitor of low capacitance C and the connecting wires act as a low inductance L. The frequency of the oscillations is given by $ν = \frac{1}{2 π \sqrt{LC}}$

The detector is in the form of an unclosed metallic ring having small metallic spheres with a small gap.The magnetic field produce by the oscillating current is perpendicular to the plane of the ring. The oscillating magnetic field linked with the ring, produces large induced emf which causes a spark to appear at the spheres of the detector.

Thus, he could be able to transport a radio frequency spark to a distance od several meters.

Draw a labeled diagram of Hertz's experimental set up to produce e.m waves. Explain the generation of electromagnetic waves using this setup.

Important Questions on Electromagnetic Waves

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