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प्रश्न
Discuss the Hertz experiment.
उत्तर
The existence of electromagnetic waves was experimentally confirmed by Hertz in 1888.
Construction:
- It consists of two metal electrodes (S1, S2) which are made of small spherical metals.
- These are connected to large spheres (A, B) and the ends of them are connected to an induction coil with a very large number of turns (H.T. Coil)
Working:
- The induction coil produces a very high electromotive force (emf)
- Since the coil is maintained at very high potential are between the electrodes (S1, S2) get ionized and spark is produced.
- The gap between the ring type electrode kept at a distance also gets spark.
- This implies that energy is transmitted from an electrode (S1, S2) to the receiver
(x, y) - If the receiver (x, y) is rotated by 90° no spark is observed by the receiver.
- This confirms that electromagnetic waves are transverse.
- Hertz produced radio wave which also travels with the velocity of light (3 × 108 ms-1).
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