Question

Consider the 3 m long lossless air-filled transmission line shown in the figure. It has a characteristic impedance of $120\pi \Omega$ , is terminated by a short circuit, and is excited with a frequency of 37.5 MHz. What is the nature of the input impedance $\left(Z_{in}\right)$ ?

Answer 1

Ans : (d)


$I=3m$

f = 37.5 MHz

$\Rightarrow \lambda =\frac{3\times {10}^8}{37.5\times {10}^6}=8m$

$Z_{in}\left(SC\right)=j{Z}_{0}tan\beta l=j120\pi tan\frac{2\pi }{8}\cdot 3$

$=-j120\pi \Omega$