​ In air, a lossless transmission line of length 50 cm with L = 10μH/m, C = 40PF/m ​

Question

In air, a lossless transmission line of length 50 cm with L = 10\(\mu\)H/m, C = 40PF/m is operated at 25 MHz. It’s electrical path length is 

(a) 0.5 meters 

(b) \(\lambda\) meters 

(c) \(\frac{\pi}2\) radians 

(d) 180 degrees

Answer 1

(c) \(\frac{\pi}2\) radians 

Electrical path length = \(\beta\)l radians

velocity v = \(\frac{1}{\sqrt{LC}}\) = \(\frac1{\sqrt{10\times10^{-6}\times40\times10^{-12}}}\)

 \(\beta\)l = \(\frac{2\pi}{\lambda}\) x l

= \(\frac{2\pi}{2}\) x \(\frac{50}{100}\)

  \(\frac{\pi}2\) radians