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SECTION B [30]
The questions in this section will be marked in full, and all steps must be shown.
QUESTION 10 [9]
A source with vg (t) = cos(106t + 30˚) V and Zg = 50 Ω is connected to a 50 Ω lossless transmission line of length l
= 3 m that is terminated in a 100 Ω load. The transmission dielectric has εr = 2.25. Distance along the transmission
line is described in terms of the coordinate z, defined such that the load is at z = 0 and the input terminals to the line
at z = -l.
(a) Find Zin, the input impedance of the line, in rectangular form. [1]
(b) Find I (z  1.5 m) , the total phasor current on the line at a position 1.5 m away from the load, in polar form
(give the angle in degrees). [6]
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(c) Find the power reflected from the load. [2]
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