Topic: Electromagnetics
The characteristic impedance of a lossless transmission line is given by
- A. Z = $\sqrt{LC}$
- B. Z = $\sqrt{C/L}$
- C. Z = LC
- D. Z = $\sqrt{L/C}$
Answer: D. Z = $\sqrt{L/C}$
Explanation: For a transmission line, the characteristic impedance Z0 = $\sqrt{(R + jwL}$ / (G + jwC)). For a lossless line, the resistance (R) and conductance (G) are zero. Thus, Z0 simplifies to $\sqrt{jwL / jwC}$ = $\sqrt{L / C}$.