Tamil Nadu Board of Secondary EducationHSC Science Class 12

Explain the importance of Maxwell’s correction. - Physics

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Long Answer

Explain the importance of Maxwell’s correction.

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Solution

  1. Ampere’s law says that only an electric current can produce a magnetic field. If Ampere’s law alone is true, there will not be any radiation.
  2. Maxwell’s correction term `(mu_0epsilon_0 ("d"phi_"E")/"dt")`
  3. In ampere’s law ensures that time-varying electric field or displacement current can also produce a magnetic field.
  4. Though conduction current is zero in an empty space displacement current does exist. So Maxwell equation becomes
    `oint vec"B" * vec"dI" = mu_0epsilon_0 ("d"φ_"E")/"dt"`
  5. Faraday’s law this time-varying magnetic field produces again time-varying electric field and so on.
  6. The coupled time-varying electric and magnetic fields travel through empty space with the speed of light and is called an electromagnetic wave.
  7. Even though Maxwell initially started with a purely symmetry argument his correction term explains one of the important aspects of the universe namely the existence of electro magnetic waves.
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Chapter 5: Electromagnetic waves - Evaluation [Page 283]

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Tamil Nadu Board Samacheer Kalvi Class 12th Physics Volume 1 and 2 Answers Guide
Chapter 5 Electromagnetic waves
Evaluation | Q III. 5. | Page 283

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