COMEDK · Physics · 24. Electromagnetic Waves
An electromagnetic wave of frequency \(3 \mathrm{~MHz}\) passes from vacuum into a dielectric medium \((\mu_r=1)\) of relative permittivity 4.0. Then,
- A Wavelength and frequency are unchanged
- B Wavelength doubled and frequency remains unchanged
- C Wavelength is halved and frequency remains unchanged
- D Wavelength is halved and frequency is doubled
Answer & Solution
Correct Answer
(C) Wavelength is halved and frequency remains unchanged
Step-by-step Solution
Detailed explanation
The frequency of an electromagnetic wave is determined by the source and remains constant when the wave travels from one medium to another. Thus, the frequency remains \(3 \text{ MHz}\). The speed of an electromagnetic wave in vacuum is…
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