write a note on Hertz's experiment for the production of EM waves (electromagnetic wave).?
Answers
Write a note on Hertz's experiment for the production of EM waves (electromagnetic wave).?
→ Hertz's experiment was based on the principle that a vibrating electric charge radiates electromagnetic waves. The experimental arrangement is shown in the figure provided with the answer ( Check the attachment given with this answer ) .
→ There are two large metallic plates A and B connected to an induction coil. Two metallic spheres I and I' are connected to metallic plates. These spheres are separated by a small air gap. There is production of spark between the spheres. This spark gives rise to oscillations which ends out electromagnetic waves.
Hope it helped u.
Answer:
Principle
Hertz experiment is based on the principle that an oscillating electric charge radiates electro-magnetic waves.
Construction
It consists of two large square metal plates P1 and P2 placed about 60 cm apart. The plates are connected to two highly polished metal spheres S1 and S2 through thick copper wires. An induction coil is employed to supply high potential difference across the spheres.
Working
When a high potential difference is applied across S1 and S2, the air between the spheres gets ionized and electromagnetic waves of high frequency is radiated. This generated em-wave is detected using a detector placed at a distance from the spheres. The frequency of oscillation is given by the equation
where, L is the inductance of the coil and C is the capacitance of the two plates P1 and P2
The detector is a metal ring connected to two small spheres C and D with a small gap in between. The detector is placed in such an alignment that the magnetic field produced by the oscillating charge (current) is perpendicular to the plane of the ring. The spark produced between S1 and S2 radiates em waves and as a spark is initiated between C and D.
Note
The electromagnetic radiation produced by this experiment is significant only if the distance to which the charge oscillates is comparable to the wavelength of radiation.
The frequency of these oscillations is 5 x 107 Hz.
Wavelength of the obtained radiation is 6 m.
The resistance of the metal ring, of the detector, is of low resistance.