Electrical Engineering Answers

A long transmission line delivers 10 kW into an antenna; at the transmitter end, the line current is 5 A, and at the coupling house (load) it is 4.8 A. Assuming the line to be properly terminated and the losses in the coupling system to be negligible, what is the power lost in the line?

Let, the bandwidth of the message signal is 500 Hz. What should be the

value of ωc to avoid overlap in the spectra at DSB-SC modulation? Where

ωc = frequency of the carrier signal.

For an AM communication the modulating signal is given as

m(t) = 5 cos(2π500t) + 10 cos(2π1000t) + 20 cos(2π1500t) and the carrier

signal is given as c(t) = 50 cos(2π105t). Calculate:

(i) Upper Side band power

(ii) Lower Side band power

(iii) Total power delivered to the load of 1000Ω

(iv) Transmission efficiency

A 4-pole DC shunt generator with wave connected armature has 41 slots and 12 conductors per slot. Ra=0.5ohm, Rsh=200ohm and flux per pole is 125mWb. When the generator is driven at 1000rpm, calculate the voltage across and current through a 10ohm load resistance connected across the armature terminals and also calculate power developed by the armature.

Design a low pass T- section filter with cutoff frequency 2.5kHz to work into 1kohm load computer attenuation dB at twice the cutoff frequency .Find the characteristic impedance and phase shift 80% of the cut off frequency