Electrical Engineering Answers

Find the charge flowing q(t) through a device if the current is i(t) = 10 e-30t sin 40t A,

q(0) = 0

Plot the variation in impedance wrt the frequency in a series RLC circuit fed with an  alternating current supply of variable frequency.

Calculate the characteristic impedance for a line that exhibits an inductance of 4 nH/m and 1.5 pF/m

In an AM radio receiver the received signal is given as X1(t)

m(t)cos(2π10000t) where m(t) represents the message signal. We want to

translate the received signal to X2(t) = m(t)cos(2π5000t). Explain how can we

perform the above task.[You have to show the block diagram]

With a neat sketch explain the three phase transformer connections.

The device parameters for an n-Channel JFET are: Maximum current iDSS = 10mA. Pinch off voltage, Vp = - 4V Calculate the drain current for (a) VGS = 0 (b) VGS - 1.0v (c) VGS = - 4V.

Explain the difference between installation and insulation.

What is the purpose of each of the two capacitors normally used in this circuit? 

A. State Faradays law of electromagnetic induction.

B. Explain the basic operation of a generator using a suitable diagram to support your answer.

c. List Two (2) pros and cons for:

i. Compact Fluorescent Lights (CFL) ii. Light Emitting Diodes (LEDs)

A. There are specific tests that must be performed at the end of an installation State the purpose for performing each of the following tests:

 i. Polarity test ii. Earth continuity test iii. Insulation resistance test