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The intrinsic impedance of free space is

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UPSC ESE Electronics & Communication 2022 Official Paper
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  1. 107 Ω
  2. 214 Ω
  3. 377 Ω
  4. 754 Ω

Answer (Detailed Solution Below)

Option 3 : 377 Ω
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Detailed Solution

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Intrinsic Impedance of free space is given by

\(\eta = \frac{{\sqrt \mu }}{{\surd \epsilon}}\)

μ = 4 π x 10-7 H/m

ϵ = 8.85 x 10-12 F/m

\(\eta = \frac{{\sqrt {4{\rm{\;\pi \;x\;}}{{10}^{ - 7}}{\rm{\;}}} }}{{\sqrt {8.85{\rm{\;x\;}}{{10}^{ - 12}}{\rm{\;}}} }} = 376.7 \approx 377\;{\rm{\Omega }}\)
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