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Electronics Engineering
Electronics Engineering is a branch of engineering that deals with practical applications of electronic components, devices, systems, or equipment. Electronics are devices that operate on low voltage sources, as in electron tubes, transistors, integrated circuits, and printed circuit boards and use electricity as part of its driving force.
24,372 Questions
Why must voltmeter be connected in parallel with the circuit component?
Because, by definition, a voltage is the difference in potential between two different points. So the voltmeter must be connected across those points in order to measure that voltage -i.e. in parallel with the points.B
What are the advantages of active filters over passive filters?
Active filters have three main advantages over passive filters:
- Inductors can be avoided. Passive filters without inductors cannot obtain a high Q (low damping), but with them are often large and expensive (at low frequencies), may have significant internal resistance, and may pick up surrounding electromagnetic signals.
- The shape of the response, the Q (Quality factor), and the tuned frequency can often be set easily by varying resistors, in some filters one parameter can be adjusted without affecting the others. Variable inductances for low frequency filters are not practical.
- The amplifier powering the filter can be used to buffer the filter from the electronic components it drives or is fed from, variations in which could otherwise significantly affect the shape of the frequency response.
Are the circuits at homes connected in series or parallel and why?
They're connected in parallel, this is so that everything connected to the circuits will receive the same voltage. Also, if everything was connected in series, if one of the components died, everything would be dead (think of christmas lights)
Kirchoff's Voltage and Current Laws apply to all ac circuits?
Kirchoff's Voltage and Current Laws apply to all AC circuits as well as DC circuits. Other laws, such as Ohm's law and Norton and Thevanin equivalents apply equally as well.
The complicating factor is that, at AC, current and voltage are not usually in phase with each other, unless it is a simple resistive circuit. That makes the math harder, but it does not make it invalid or impossible.
Comparator 1 has a threshold input (pin 6) and a control input (pin 5). In most applications, the control input is not used, so that the control voltage equals +2/3 VCC. Output of this comparator is applied to set (S) input of the flip-flop. Whenever the threshold voltage exceeds the control voltage, comparator 1 will set the flip-flop and its output is high. Ahigh output from the flip-flop saturates the discharge transistor and discharge the capacitor connected externally to pin 7. The complementary signal out of the flip-flop goes to pin 3, the output. The output available at pin 3 is low. These conditions will prevail until comparator 2 triggers the flip-flop. Even if the voltage at the threshold input falls below 2/3 VCC,that is comparator 1 cannot cause the flip-flop to change again. It means that the comparator 1 can only force the flip-flop's output high.
To change the output of flip-flop to low, the voltage at the trigger input must fall below + 1/3 Vcc. When this occurs, comparator 2 triggers the flip-flop, forcing its output low. The low output from the flip-flop turns the discharge transistor off and forces the power amplifier to output a high. These conditions will continue independent of the voltage on the trigger input. Comparator 2 can only cause the flip-flop to output low.
From the above discussion it is concluded that for the having low output from the timer 555, the voltage on the threshold input must exceed the control voltage or + 2/3 VCC. They also turn the discharge transistor on. To force the output from the timer high, the voltage on the trigger input must drop below +1/3 VCC. This also turns the discharge transistor off.
A voltage may be applied to the control input to change the levels at which the switching occurs. When not in use, a 0.01 nano Farad capacitor should be connected between pin 5 and ground to prevent noise coupled onto this pin from causing false triggering.
Connecting the reset (pin 4) to a logic low will place a high on the output of flip-flop. The discharge transistor will go on and the power amplifier will output a low. This condition will continue until reset is taken high. This allows synchronization or resetting of the circuit's operation. When not in use, reset should be tied to +VCC.
Applications of matrices in the field of electronics and communication engineering?
A prime example of matrices (plural) being used in computers if in computer graphics and rendering where matrices are used in 3D work for transformations like rotation, scaling and translations. Although I'm sure there are plenty more fields in computer science where matrices may be used.
RADAR is used for Radio Distance and Direction.
Radar is an example of the fourth real dimension of Quaternion "space-time", real dimension r= ct. Space is quaternion with three vector dimensions Ix, Jy and Kz and one real dimension r=ct. RADAR is a manifestation of this real dimension.
What is a capacitor and how does it work?
A capacitor is an electronic device for accumulating and holding a charge of electricity. It consists of two equally charged conducting surfaces having opposite electrical polarity which are separated by a dialectric insulator.
It is a passive electronic component that stores energy in the form of an electrostatic field.
Another Answer
A capacitor is a circuit component that stores energy. It consists of two, parallel, conducting surfaces, called 'plates', separated by an insulator or dielectric. When attached to a d.c. supply, negative charges are transferred from one plate to the other and, if it is then removed from the d.c. supply, the one plate remains negative with respect to the other.
It's a misconception to say that a capacitor 'stores charge', because the amount of charge on the plates remains the same before and after 'charging'! It is more accurate to say that it stores 'separated charges' but, strictly speaking, it's energy that's being stored.
passive two-terminal electrical component used to store energy electrostatically in an electric field this is an instrument that is used to store charge
capasitor is electronic device his work useful for electronic gadjet and also useful electronic machine ther are six type of capasitor ceramic capasitor:"electrolightic capasitor:"plastic film rasistor:"polishtor film rasistor:"propfylin capasitor:"metalesed capasitor
Why capacitor allows ac and not dc?
CAPACITOR BLOCKS DC SUPPLY .THERE ARE MAINLY TWO ANSWERS
1.CAPACITIVE REACTANCE Xc=1/( 2*3.1416*F*C) , HERE THE FREQUENCY OF DC SUPPLY IS ZERO .HENCE THE REACTANCE VALUE IS INFINITY .SO IT BLOCKS THE DC SUPPLY.
2.CURRENT THROUGH A CAPACITOR IS PROPORTIONAL TO THE RATE OF CHANGE OF CURRENT . BUT IN THE CASE OF DC SUPPLY, THE RATE OF CHANGE OF CURRENT IS ZERO. HENCE THE CAPACITOR CURRENT IS ALSO ZERO.
H.L.kiran
RF signals are generally described as alternating current electical signals with a frequency range starting just above the highest frequency that can be heard, about 20,000 cycles per second, and going as high as 10,000,000,000,000 cycles per second, which is considered to be in the lowest region of infrared light/radiation. These are electrical and electromagnetic signals carried in wire, waveguides, through the air, or in space.
The answer is vague, and so is the question. Here are some examples of everyday RF signals:
10 to 80 KHz range used by governments to communicate with submarines.
90 to 110 KHz signals used by the old LORAN navigation system.
530-1700 KHz band, approximately, as used for AM /broadcast entertainment radio.
3000 to 30,000 KHz (3 to 30 MHz) range of RF signals, commonly called the "shortwave radio band".
27.185 MHz is CB radio channel 19 in the uSA.
88 to 108 MHz as used by FM broadcast radio in the USA.
300 to 500MHz as very commonly used by city, fire, military, and police.
2500 to 30,000 MHz (2 to 30 GHz) used by satellites.
Higher than 50 GHz is mostly experimental and military.
What is the resistance of the circuit if current flow is 6 amperes in a 120-V circuit?
Google Ohms Law. It will give you all the formulas you need to compute Ohms,Volts and Amps. Simple formulas :-)
What is the configuration of cascade amplifier?
In a cascade amplifier, two identical or non identical amplifiers are cascaded ,i.e., connected in series through a capacitor. They are mostly common emitter amplifiers that are cascaded together.The final gain of the cascaded amplifier is the product of the first amplifier's gain and the second amplifier's gain. However, the bandwidth of the cascaded version becomes lesser than the individual gains.
What makes a good electrical conductor?
number of electrons capable of freely moving in the outermost shell of an element. eg. Copper
Disadvantages of RFID:
i. Expensive compared with Bar code
ii. Bulkier, due to embedding of electronic components in the tag. However, with advanced techniques, it is possible to reduce the size, and weight of the tags to a large extent.
iii. Prone to physical/electrical damage due to environmental conditions. For example, tags that are subjected to space exploration may encounter extreme temperatures. The tags required to be designed for a given application, and may be costly when designed for use under extreme environmental conditions.
How does ic 7405 work with pin configuration?
The 7405 is a hex inverter with open collector-outputs, the I/O's is as follow:
Input Inverted output
Pin1=A1 Pin2=Y1
Pin3=A2 Pin4=Y2
Pin5=A3 Pin6=Y3
Pin9=A4 Pin8=Y4
Pin11=A5 Pin10=Y5
Pin13=A6 Pin12=Y6
Power pins
Pin14=Vcc +
Pin 7=GND
When the voltage across a resister is doubled the current will?
If I0 = V/R, then Inew = (2*V)/(.5*R) = (2 / .5) * (V/R) = 4 *V/R = 4 * I0
What are the advantages of an analog signal?
Though we, as people, can interpret digital signals (if we train ourselves to do it - like Morse code), we do better with analog signals. Music and speech as well as most other sound is analog. We interpret analog audio signals almost instantly, and without even thinking about it. Without analog signals, most of our listening activities are for nothing. Let's take sound to the electronics forum. Electronically, a digital signal requires that we convert our analog signal to a digital one in an audio-to-digital converter (AtoD). And we have to convert it back at the other end. We can do all this, but it takes extra stages and effort to make it happen. Certainly it's the only way we can move all the signals we need to move, like with cell phone traffic. Without digital techniques, we'd be dead in the water trying to serve all the cellular customers we serve, but voice traffic starts and ends as analog signals 'cause we human critters can relate to them better.
When an AM signal is received, the receiver must perform a converse process to get the original signal ( Information Signal ) back .
This process is known as detection or demodulation, the simplest process which is used widely in AM radios is the Envelop Detector .
Envelop Detector is an electronic circuit which is used to recover ( Demodulate ) the original signal in AM systems, its constructed from just one diode, one capacitor and one resistor .
This is essentially just a halfwave rectifier which charges a capacitor to
a voltage = the peak voltage of the AM signal .
However .. the output of the detector follows the envelop of the modulated signal.
On the positive cycles of the input signal, the diode conducts and the capacitor charges
up to the peak voltage of the input signal.
As the input falls below this peak value, the diode is cut off, because the capacitor
voltage is greater than the input signal voltage, thus causing the diode to open.
The capacitor now discharges through the resistor at slow rate .
The discharge process continues until the nest positive half-cycle. When the input signal
becomes greater than the output across the capacitor, the diode conducts again and the process is repeated .
Why rectangular wave guide is preferred over a square waveguide for usual microwave transmissions?
A square waveguide does not allow single mode operation as for example fc(TEmn)=fc(TEnm).
A current is measured in which unit?
The Ampere, also in shortened form 'Amp' or "A". It commonly uses the symbol "I" in calculations, hence Ohm's law is in the form V = I x R
Compare the characteristics of a silicon and germanium diode?
Potential barrier of silicon is 0.7, whereas potential barrier of germanium is 0.3
What is a measure of the total bandwidth of data moving between the module and the CPU?
A CPU consists 3 units and i assume a module is an external device of some kind. In that is the case then the limitation or bandwidth with which data can be transferred back and forth safely namely the I/O. The data will be limited by layout of the board and RAMS speed more then the CPU that runs much faster but usually is waiting for data
