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the later part of the 19th century. It was the result of the synthesis of various facts and laws pertaining to electricity and magnetism, like Gauss' law, Ampere's law, Faraday's law, the closed nature of magnetic field lines etc. by a British scientist James Clerk Maxwell in form of Maxwell's equations. These are the differential equations which interconnect electric and magnetic field parameters through differential equations. Examination of these equations in terms of symmetry between electric and magnetic phenomena also lead to the famous contribution due to Maxwell of the term called the displacement current a term which provided
the missing aspect to complete the symmetry." (b) Satish K. Gupta, op.cit., p. 731
"These equations govern the behaviour of electric and magnetic fields. Maxwell showed that these equations predict the existence of electromagnetic waves, which propagate through the space in the form of varying electric and magnetic fields. He also showed that these waves are transverse in nature and travel with the speed of light. Gauss's law in electrostatics. It states that the total electric flux through any closed surface is alwys equal to 1/e, times the net charge enclosed by the surface. 2. Gauss's law in magnetism. It states the net magnetic flux crossing any closed surface is always zero. A direct consequence of Gauss's magnetism is that an isolated magnetic monopole does not exist. 3. Faraday's law of electromagnetic induction. It states that the induced em.f. produced in a circuit is numerically equal to rateof change of magnetic flux through it. In this form, the law states that the line integral of electric field along a closed path is equal to rate of change of magnetic flux
through the surface bounded by that closed path." 50. Ibid., p. 731
Nature of Electromagnetic Waves "From Faraday's law of electromagnetic induction, it was concluded that a magnetic field changing with time at a point in space produce an electric field at that point. On the other hand, Maxwell's concept of displacement current led to the conclusion that an electric field varying with time at a point produces a magnetic field at that point. This symmetry in the laws of electricity and magnetism leads to the conclusion that a time varying electric field gives rise to a time varying
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THE FUT Biat 120-121
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