# Electronics and Communication Engineering - Electromagnetic Field Theory - Discussion

Discussion Forum : Electromagnetic Field Theory - Section 1 (Q.No. 1)
1.
ZL = 200 Ω and it is desired that Zi = 50 Ω The quarter wave transformer should have a characteristic impedance of
100 Ω
40 Ω
10000 Ω
4 Ω
Explanation:

Z0 = Zi . ZL

Discussion:
10 comments Page 1 of 1.

RISHI NIGAM said:   2 years ago
Here, Zin=z0^2/zl for quarter-wave transformer.
(1)

Meiyyappan said:   5 years ago
Thanks for the explanation @Phyaffin.

Manjunath G Hegde said:   5 years ago
Thanks @Phyaffin.

Himanshu said:   6 years ago

Siri said:   6 years ago
Thank you for the explanation.

Mohan said:   6 years ago
Thanks for the explanation.

Phyaffin said:   7 years ago
Zi = input impedance at the input of quarter wave transformer.
The above two have to be matched, so that what should be the characteristic impedance of QWT.

We have, Zo^2 = sqrt(ZL * Zi).

Therefore, Zo = 100 Ω.
(1)

Nitin said:   8 years ago
What is the importance of "quarter wave" which is mentioned in the question?

MD ASIF said:   8 years ago