The propagation constant of a transmission line is \(0.15 \times {10^{ - 3}} + {\rm{j}}1.5 \times {10^{-3}}\). The wavelength of the travelling wave is

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  1. \(\frac{{1.5 \times {{10}^{ - 3}}}}{{2\pi }}m\)
  2. \(\frac{{2\pi }}{{1.5 \times {{10}^{ - 3}}}}m\)
  3. \(\frac{{1.5 \times {{10}^{ - 3}}}}{\pi }m\)
  4. \(\frac{\pi }{{1.5 \times {{10}^{ - 3}}}}m\)

Answer (Detailed Solution Below)

Option 2 : \(\frac{{2\pi }}{{1.5 \times {{10}^{ - 3}}}}m\)
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Propagation constant is a measure of changes in a sinusoidal electromagnetic wave in terms of amplitude and phase, while propagating through a medium. This can be a transmission line or free space.

Propagation constant (γ) = α + jβ

α = Attenuation constant, it causes the signal amplitude to decrease while propagating through a transmission line.

β = Phase constant, it is the imaginary component of the propagation constant. It gives us the phase of the signal along a transmission line, at a constant time.

\(β = \frac{\omega }{{{V_p}}} = \frac{{2\pi f}}{{{V_p}}}=\frac{{2\pi }}{{{λ}}}\)

λ is the wavelength

Calculation:

propagation constant of a transmission line is 0.15 × 10-3 + j1.5 × 10-3.

β = 1.5 × 10-3.

Wavelength \(\lambda = \frac{{2\pi }}{\beta } = \frac{{2\pi }}{{1.5 \times {{10}^{ - 3}}}}m\)

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