JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
An electromagnetic wave of frequency \(3\, GHz\) enters a dielectric medium of relative electric permittivity \(2.25\) from vacuum. The wavelength of this wave in that medium will be \(.......\,\times 10^{-2} \, cm\)
- A \(667\)
- B \(577\)
- C \(627\)
- D \(747\)
Answer & Solution
Correct Answer
(A) \(667\)
Step-by-step Solution
Detailed explanation
\(\lambda\) in vacuum \(=\frac{c}{f}=\frac{3 \times 10^{8}}{3 \times 10^{9}}=0.1\, m\) \(\therefore \lambda\) in medium \(=\frac{0.1}{\mu}\) Where refractive index \(\mu=\sqrt{\mu_{z} \varepsilon_{z}}\) Assuming non-magnetic material \(\mu_{ r }=1\)…
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