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An open wire transmission line has primary constant
R = 20 Ω/m G = 0.3 × 103 s/km
L = 0.25 1 m H/km C = 0.1 µ F/m
at a frequency of 1 kHz its characteristic impedance is—
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- 169.73 Ω, ∠– 25º
- 238.2 Ω, ∠– 25º
- 715 Ω, ∠– 25º
- 50 Ω, ∠– 25º
Correct Option: A
We have characteristic impedance as follows
| Z0 = | √ | |
| G + jωc |
R = 20 Ω/ km,
G = 0.3 × 103 s/ km
L = 0.25 mH/ km,
C = 0.1 µF and ω = 103 Hz so we get
| Z0 = | √ | |
| 0.3 × 10−3 + j2π(103 × 0.1 × 10−6) |
| = | √ | |
| 0.30 −3 + j2π(0.1 × 10−6) |
= 169.75 ∠– 25º
