Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
Paper format. National Examinations, December 2017 — 16-Elec-A7 Electromagnetics. Three hours, closed book (one Casio or Sharp approved calculator). Eight questions of equal value; the rubric states that any five questions constitute a complete paper and that only the first five answered will be marked. All eight are solved here, because the set is a study resource rather than a sitting. Aids printed on the paper: $\varepsilon_0 = 8.85 \times 10^{-12}\ \text{F/m}$ and $\mu_0 = 4\pi \times 10^{-7}\ \text{H/m}$.
Reference texts. D. M. Pozar, Microwave Engineering, 4th ed. (transmission-line transients, stub networks, waveguides); W. H. Hayt and J. A. Buck, Engineering Electromagnetics, 9th ed. (plane waves, polarisation, Biot–Savart, inductance); M. N. O. Sadiku, Elements of Electromagnetics, 7th ed. (magnetostatics, guided waves); F. T. Ulaby and U. Ravaioli, Fundamentals of Applied Electromagnetics, 8th ed. (wave polarisation, radiation); C. A. Balanis, Antenna Theory: Analysis and Design, 4th ed. (short-element fields).
Constants used throughout. The aid sheet's $\varepsilon_0$ and $\mu_0$ give $c = 2.9986 \times 10^{8}\ \text{m/s}$ and $\eta_0 = 376.82\ \Omega$, while every round figure the paper quotes (10 km at $3 \times 10^{8}\ \text{m/s}$, 300 and 600 MHz, 10 GHz giving a 3 cm wavelength) is built on $c = 3.00 \times 10^{8}\ \text{m/s}$ and $\eta_0 = 120\pi = 376.99\ \Omega$. Those are the values used below; the two sets differ by less than 0.05 % and no answer or conclusion changes.
