________________
55. (a)
2. Experiment of Hertz Althougth existanc: of the electromagnetic waves theoritically deduced, an experimental demonstration that such waves can be produced in laboratory remaind to be achieved. It is said that Maxwell himself was very much desirous of being a witness to such an achievement during his lifetime. Thirty-two years after the proposition of electromagnetic field, equations of Maxwell, Hertz demonstrated production of such waves in laboratory. Ibid., pp. 98, 99% “Characteristics of Electromagnatic Waves "Electromagnetic waves have the following characteristics : (1) At regions far from the source the electric and the magnetic
field, vectors oscillate in the same phase. (2) The directions of oscillations of the electric and the
magnetic fields are mutually perpendicular; and are in a plane prependicular to the direction of propagation of the
wave. (3) These waves are non-mechanical and of transverse type. (4) Their velocity in free space (vacuum) is given by
c = 3 x 108 ms Light waves have the same velocity in vacuum as experi
mentally measured. (5) The velocity of electromagnetic waves depends upon the
electromagnetic properties of that mcdium. Satish K. Gupta, p. 735_-. Properties of Electromagnetic Waves A sew important properties of electomagnetic waves are as given
below : (1) Electromagnetic waves propagate in the form of varying
electric and magnetic fields, such that the two fields are perpendicular to each other and also to the direction of propagation of the wave. In other words, electromagnetic
waves are transverse in nature. (2) Electromagnetic waves are produced by accelerated charges. (3) Electromagnetic waves do not require any material medium
for their propagation.
(b)
114
Jain Educationa International
For Personal and Private Use Only
www.jainelibrary.org
