Explore BrainMass

Electrical Engineering

Electrical engineering is a field of study that deals with the study and application of electricity, electronics and electromagnetism. After the invention of electric telegraph, the telephone and electric power use, electrical engineering came to be a field of study. Today, electrical engineering has many subfields including electronics, digital computers, power engineering, telecommunications, control systems, RF engineering and signal processing.

Electrical engineers have an academic degree with a major in electrical engineering, electronics engineering or electrical and electronic engineering. Fundamental principles taught are the same throughout each program. The length of the degree is typically four or five years. These degrees covers an extensive amount of physics, mathematics, computer science, project management and variety of topics in electrical engineering.

Most electrical engineers understand basic circuit theory. However, the theories employed by engineers depend upon that work they do. Circuit theory may not be relevant to a person designing telecommunication systems that use off the shelf components. The most important skills for electrical engineers are strong numerical skills, computer literacy and the ability to understand the technical language and concepts that relate to electrical engineering.

Categories within Electrical Engineering

Computer Engineering

Postings: 43

Computer engineering is a field of study that integrates electrical engineering and computer science to develop computer hardware and software.

Electronic Engineering

Postings: 249

Electronic engineering is a discipline where non-linear and active electrical components are utilized to design electronic circuits, devices and systems.

Power Engineering

Postings: 145

Power engineering deals with the generation, transmission and distribution of electric power as well as the electrical devices.

Drawing fault tree based on data and estimating fault rate

I need solutions to the question a) only, please. For the system shown below where each labeled box indicates a valve that is normally open: (a) Draw a fault tree for the top event "no flow out of the system." (b) Find the minimal cutsets (c) Find the exact top event probability using the basic event probabilities given

Multiple electrical signal, level, noise calcualtions

1. FIGURE 1 shows the block diagram of a superhetrodyne radio receiver. In a test a 20 V signal was fed from the aerial into the first stage of the receiver, a radio frequency amplifier. This signal is then passed through several stages of the receiver to eventually appear at the input to the AM detector. For the AM detector

Diodes, Transistors (Including BJT) and Current Mirrors

Show all logic/work/sources leading up to the conclusions drawn for each problem. 1. One simplified model of a forward conducting Silicon diode's behaviour is to consider the diode to be equivalent to a series combination of a low resistance, a 0.7V fixed voltage source, and an ideal diode. Explain how this model is a reaso

Control of an electric heating system

Attached is a drawing showing the block diagram of the control of an electric heating system. The heater is driven from a voltage-controlled power supply, the voltage V1 being derived from a potentiometer. The output temperature, 0 degree, is subject to disturbances, 0D, because of changes in the ambient temperature. It is propo

Proportional Plus Derivative Control

The attached drawing shows a proportional plus derivative controller that has a proportional band of 20% and a derivative action time of 0.1 minutes. Construct the shape of the output waveform for the triangular input waveform shown, if the input rises and falls at the rate of 4 units per minute.

Electrical Service

(a) State the type of motor starter circuit shown in FIGURE 2(a) (see attached file). (b) The ends of the motor stator coils are shown as U1 and U2, V1and V2 and W1 and W2 Referring to FIGURE 2(b) (see attached file), sketch the connections of the windings between the contactors C1 and C3 for starting and C1 and C2 for runni

Amplifier Circuit Analysis

FIGURE 4 shows an amplifier circuit. Write a short report on the operation and performance of the circuit. In completing the report you should: - Explain the operation of the circuit and in particular the role of resistors R1 and R2. - Build the circuit in PSpice and use it to determine: (i) the quiescent value of Vout (ii)

Drawing Impedance Diagrams

A 415 V, 3-phase generator supplying a 3-phase 415/110 V transformer. Draw the individual and combined impedance diagrams to a base of 10 kVA. Determine the system fault kVA and the fault currents at the 415 V and 110 V busbars for short circuit faults on the transformer input or output terminals. Work in p.u. values of impedanc

Computing the Z-transform

1. For a discrete-time signal x[n] with the z-Transform X(z) = z/(8z^2-2z-1), find the z-Transform, V(z) for the signal v[n] = x[n] * x[n]. 2. Compute the unit-pulse response h[n] for the discrete-time system y[n+2]2y[n+1]+y[n]=x[n] (for n = 0, 1, 2, 3). 3. Compute the z-transform of the discrete time signal define

Fourier transform problems

1. A continuous time signal x(t) has the Fourier transform X(ω) = 1/(jω+b) where b is a constant. Determine the Fourier transform for v(t) = t^2 x(t). 2. A continuous time signal x(t) has the Fourier transform X(ω) = 1/(jω+b) where b is a constant. Determine the Fourier transform for v(t) = x(t) * x(t). 3. C

Show the resulting diagram of access right dependencies.

Figure 5.14 (in the attachment) shows a sequence of grant operations for a specific access right on a table. Assume that at t = 70, B revokes the access right from C. Using the conventions defined in Section 5.2, show the resulting diagram of access right dependencies.

Noise Level to Fall Below Background noise in a Wind Turbine

As a rule of thumb, the perceived noise from a source falls by 6 dBA with every doubling of the distance from the source. If a 1 MW wind turbine (FIGURE) produces 103 dBA of noise within one metre of its base, estimate the distance from the turbine at which the noise can be reckoned to have fallen below the background noise leve

Minmum gain of intermediate amplifier in superhet radio receiver

FIGURE 1 shows the block diagram of a superhetrodyne radio receiver. In a test a 20 uV signal was fed from the aerial into the first stage of the receiver, a radio frequency amplifier. This signal is the passed through several stages of the receiver to eventually appear at the input to the AM detector. For the AM detector to wor

Fouriers analysis 'inverse' function.

Question 1 Harmonic distortion is aserious problem for the electrical supply industry and can cause overheating of induction motors and transformers and cause the neutral conductor to carry more than its rated current Harmonic distortion is caused by consumer loads requiring non- sinusoidal currents. There are two main ty

Maximum Amount of Channels a Link Can Carry

A microwave radio link operates over a bandwidth of 400 MHz at C band. The link carries a number of channels of data using FDMA. Each channel has an RF bandwidth of 36 MHz and 4 MHz guard bands are needed between channels. a. What is the maximum number of channels that the link can carry? b. If half rate error correction

A DSSS-CDMA signal

a. A DSSS-CDMA signal has a chip sequence that is 10,000 chips in length. The sequence repeats every millisecond. What is the chip rate? b. What is the message signal rate of the signal in part (a) above? c. The transmitter and receiver for the signal in part (a) above are both stationary so there is no Doppler shi

Radio Networks

A radio network is set up with 50 mobile transmit-receive units and a central hub station.The network has ten RF channels for transmissions to the mobile units and ten RF channels for transmissions from the mobile units to the central hub. The network operates in the uhf band.The hub station allocates frequencies to the mobile

TV Video Signals

a. A cable TV company delivers video signals over coaxial cable to individual houses. Video signals occupy a bandwidth of 6 MHz and are stacked in frequency from 50 MHz to 656 MHz without guard bands. There are 100 video channels numbered 1 through 100. Is this system using FDM or FDMA? b. When NTSC analog TV signals are se

Local Oscillator Frequency, Image Frequency, and Attenuation

A radio receiver for the AM broadcast band covers the frequency range 550 to 1600 kHz. The IF frequency is 455 kHz and the local oscillator is above the received signal frequency. a. What is the frequency range for the local oscillator of the AM radio? b. The AM radio is tuned to a weak signal at 1260 kHz. What is the

A radio receiver is tuned to an FM station at 93.7 MHz

A radio receiver is tuned to an FM station at 93.7 MHz. (That means the carrier frequency is 93.7 MHz and sidebands extend each side of the carrier). The bandwidth of the FM signal is 180 kHz. The receiver has an IF amplifier with a center frequency of 10.7 MHz. The signal from the radio's antenna is first amplified in an

Two Port Network - Parameter Matrix

Please see the attached file on a Two port network. I have attached examples of study topics. Please show detailed work of the questions with narratives to show development and transposition of formula where required so I can follow and learn a fully worked out example. Please include all calculations and work.

MOSFET Analysis

A) In comparing the behaviour of an n-channel MOSFET with a p-channel device having identical geometry and threshold voltage, it is found that the n-channel FET has a greater drain current than that of the p-channel FET. State why this should be so and give one other characteristic in which the two devices would differ. B) In

JFET Analysis

FIGURE 1 shows a single-stage JFET amplifier circuit. The n-channel JFET has the ratings and characteristics given in the table below. Show that the quiescent gate-to-source voltage is given by: V_GSQ = 2.57 - I_DQR_S Determine the maximum quiescent drain current and drain-to-source voltage of the JFET, using the 'square

NEXT and FEXT crosstalk calculations

For a lossless line: The characteristic impedance is given by Zo=sqrt(L/C) and the velocity of propagation by Vp=1/(sqrt(L*C)) Where L and C are, respectively, the line's inductance and capacitance per metre length. A transmission line is formed by two identical parallel tracks in a printed circuit board, as depicted in the a