Electronics Engineering

Arif Ullah khan utman kheel

this is because for conductor E parallel is zero this means that the surface of the wave guide is at equipotential and this potential follow the laplace equation .it means that there is no maxima and minima inside the wave guide . this means that the electric field inside zero . hence the TEM do not exist in wave guide only TE and TM can be exist . if we place some conductor in the wave guide then the conductor inside will not be equipotential and the TEM waves can be exist . like in Coaxial cables

The Fourier series is important because it allows one to model periodic signals as a sum of distinct harmonic components. In other words, representing signals in this way allows one to see the harmonics in a signal distinctly, which makes it easy to see what frequencies the signal contains in order to filter/manipulate particular frequency components.

the function of an led is to give of light coming through an electrical circuit

we can do analog signal processing also but it is very expensive as comparing with digital signal processing that's why we generally choose the digital signal processing.DSP allows programmable operations.But we cannot do in ASP.

Depends on what kind of robot. A simple robot that can be easily built into different robots is the LEGO Mindstorms NXT. Go to www.lego.com for more info.

Ohms is a measure of impedance (resistance), not volume.

When we see the prefix kilo, it means times one thousand, or x 1000. If we have 9.54 kilohms, we have 9.54 x 1000 ohms = 9,540 ohms.

Paul Baran originally invented the packet switching concept in the early 1960's. Donald Davies also independently invented the idea a few years later. Then, Leonard Kleinrock conducted early research in the related field of digital message switching. He also helped build the ARPANET, the world's first packet switching network.

A diode allows only current flow in one direction under normal operation. Exceed the operating voltage and it can break down allowing bi-directional flow.

Electricity is the interaction of many components. These include electric charges, electric fields, electric potentials, electric currents, and electromagnets.

No, a Transistor operates with a modulated direct current. You need 4 Diodes to manufacture a rectifier to deliver direct current at the outlet, with alternating current at the input. A Diode is effectively a one way valve to address one halve of the cycle of the alternating current.

Resistors are quite small.

We use colour codes in order to be able to fit a lot of information in little space.

Each colour represent a number.

Each band of colour have its own representation.

On a 4 band resistor, the first two are actual values, the third is a multiplier and the fourth is accuracy.

Please check out related question and answer down below for more information.

A light switch

A Smoothing Capacitor is a capacitor which helps to smooth out fluctuations that may exist on a power supply line.

it will be the X-OR gate of D and the output Q

In a two stage RC coupled amplifier, the two transistors are identical and a common power supply is used. The input is provided to the first stage of the amplifier where it is amplified and this output is used as input for the second stage. This is amplied once again by the other transistor in the second stage and the final output is obtained. There will be a 180 degree phase shift after the first stage amplification which is nullified by the 180 degree phase shift of the second stage amplification.Thus, we obtain an output which is an amplified signal of the input and is in phase with the input signal.

A 120V power supply connected to a 30 Ohm resistor will produce 120/30 or 4 amps of current.

1. Cheap to make.

2. Little heat whilst working.

3. Low power consumption.

4. Can utilize very high frequenzies (50-100 Khz is not uncommon.)

5. Very energy-efficient when used to convert voltages or to dim light bulbs.

6. High power handling capability

7. Efficiency up to 90%

Connect ammeter in series and voltmeter in parallel to the circuit

Two good Insulators are foam and styrafoam

Delta modulation is extremely important for high-tech lives that humans live today. Delta modulation is basically analog to digital and digital to analog signal providers, allowing for radio communication devices such as TV remotes.

Copper is used the majority of the time.

Gold is sometimes because it does not corrode.

Tungsten is used in light bulbs because it is a good resistor and resists the flow of electrons.

Aluminum and silver are also sometimes used.

There is also some recent research in safely using sodium and lithium.

In earlier days of telephone networks, 48V DC was once found to be suitably high to be able to make telephone work on long telephone lines and still low enough not to cause serious danger if somebody touches the telephone wires. Telephone central offices (exchanges) so started using 48V DC. Even when newer automatic exhanges were setup, they were designed to make use of existing 48V battery sets and arrays which were available with telecom service providers. This legacy design practice has been continued and over many decades all new telecom devices have been designed to work with 48V.

The positive grounded or -48V system is also from telephone history. The negative voltage on the line was better than positive to prevent electro-chemical reactions from destroying the copper cable quickly, if cables get wet

Ans- It is because of cathodic protection. It reduces the sulphation on the battery terminals.