Asinusoidal wave on a transmission line is specified by voltage and current in phasor form:
v s(z) = v0 eαz jβ zand is (z) = i0eαz ejβz ejϕ
where v0 and i0 are both real.
(a) in which direction does this wave propagate and why?
(b) it is found that α = 0, z0 = 50 ω, and the wave velocity is vp = 2.5 x 10^8 m/s, with ω = 108 s−1. evaluate r, g, l, c, λ, and ϕ.

Apipe with an outside diameter of 15 cm is exposed to an ambient air and surrounding temperature of -20°c. the pipe has an outer surface temperature of 65°c and an emissivity of 0.85. if the rate of heat loss from the pipe surface is 0.95 kw per meter of length, the external convective heat transfer coefficient (h) is: (a) 12.5 w/m"k (b) 18.6 w/mk (c) 23.7 w/mk (d) 27.9 w/mk (e) 33.5 w/mk