What remains constant in series circuit?
A: No matter how many resistor of different value are inserted the current will remain the same for each. The voltage drop will vary with the difference in resistors and i a parallel path is found along the way the current will divide according to the resistors values
Minimum number of nand gates required to form full and half adder?
Check this link
http://www.dumpt.com/img/viewer.php?file=bd6b3mqsa66fhr6c76l1.bmp
What is the differrence of flip-flop and latch?
a group of flip-flops sensitive to pulse duration is called latch whereas a group of flip-flops sensitive to pulse transition is called a register.
What is the difference between an SCR and a TRIAC?
A thyristor is another name for an SCR, which stands for Silicon Controlled Rectifier.
Thyristors or SCRs are bi-directional devices used to control the flow of AC current. Once triggered, the device remains "on" until the next wave of current crosses zero after the trigger is removed.
For more information about thyristors or SCRs see the Related link shown below.
Compare synchronous and asynchronous operation of sequential circuits?
A Synchronous Sequential Circuit is a system whose behavior can be defined on the timing of their signals , where in the case of asynchronous sequential circuit depend upon the order in which its inputs signals change and can be affected at any instance of time .
(reference : M. Moris Mano)
Why 2 wave traps are provided in the substation?
Line trap also is known as Wave trap. What it does is trapping the high frequency communication signals sent on the line from the remote substation and diverting them to the telecom/teleprotection panel in the substation control room (through coupling capacitor and LMU).
This is relevant in Power Line Carrier Communication (PLCC) systems for communication among various substations without dependence on the telecom company network. The signals are primarily teleprotection signals and in addition, voice and data communication signals.Line trap also is known as Wave trap. What it does is trapping the high frequency communication signals sent on the line from the remote substation and diverting them to the telecom/teleprotection panel in the substation control room (through coupling capacitor and LMU).
This is relevant in Power Line Carrier Communication (PLCC) systems for communication among various substations without dependence on the telecom company network. The signals are primarily teleprotection signals and in addition, voice and data communication signals.
The Line trap offers high impedance to the high frequency communication signals thus obstructs the flow of these signals in to the substation busbars. If there were not to be there, then signal loss is more and communication will be ineffective/probably impossible.
Do led floodlights work with a photocell?
A: Photocell and LED cannot work directly because these are different devices. But yes each independently can work as a unit all you need is some buffering.
What happens when a capacitor is connected to a dc supply?
is it ? are you sure ? but i know so many circuit where capacitor is connected with ac supply .
still , if u connected a capacitor to dc supply , then :
1. if it is in SERIES with the dc supply , it will block all the dc current as capacitor
provides infinite resistance to dc current .
application : where u want to block dc current.(simple high pass filter)
2. if it is in PARALLEL with the dc supply , it will not block dc current , but if any ac
current comes out from the supply , the ac current will go through the
capacitor , as capacitor provides small resistance to ac current.
application : a) where u want to block ac current.(simple low pass filter)
b) to filter the noise (ac components) of dc supply.
What is the digital oscilloscope used for?
A cathode ray oscilloscope (CRO) is used to see the waveform of a repetitive electronic signal. The signal is amplified or attenuated as required and used to deflect an electron beam in the vertical direction. This electron beam is deflected in the horizontal direction at a suitable speed. The electron beam impinging on a phosphorescent screen enables the viewer to see the wave shape of the signal. The operation is similar to that of a TV.
Will decreasing the resistance in a circuit decrease current flow if voltage is kept constant?
You should answer this question yourself by doing a couple of examples using Ohm's law I=E/R (current equals voltage divided by resistance. Here they are: Base circuit: 10 volt supply feeding a 10 ohm resistor calculate the current... New circuit: 10 volt supply (voltage kept constant) feeding a 20 ohm resistor (increased resistance) calculate the current... Did the current increase, or decrease? This way you can prove to yourself the answer!
How does the operational amplifier work?
The operational amplifier is a device with two inputs, and one output. One input is called non-inverting, while the other is called inverting. Sometimes, there are two outputs, in which case one is also non-inverting and the other inverting.
Within the limits of the design of the operational amplifier and its circuit, the output will assume whatever state is necessary to make the two inputs equal to each other. The output goes in the same direction as the non-inverting input, or in the opposite direction as the inverting input.
Note that for the operational amplifer to work correctly, there needs to be some kind of feedback loop, usually from output to inverting input (we call this negative feedback), so that the output can track one of the two inputs in the ratio of the bridge that is setup in the circuit design.
Capacitors are used in many different ways.
Here are a few instances where they are used:
Why TEM mode does not exist in waveguide?
for TEM u need to a magnetic field (H) linked to an electric field .for this u need to a J relative to E (E=sigma J). because [curl H = J] but optical fiber is dielectric wave guide and sigma is zero and u only have dD/dt so there isn't H linked to E.
What are majority and minority charge carriers in semiconductors?
There are two recognized types of charge carriers in
semiconductors. One is
electrons, which carry a negative
electric charge. In addition, it is convenient to treat the traveling vacancies in the
valence bandelectron population (
holes) as the second type of charge carrier, which carry a positive charge equal in magnitude to that of an electron
What is encoding in digital communication?
See SSH and SSL
is the way in which information is percieved and processed.
What are the advantages and disadvantage of pulse position modulation?
advantage-its a base for all the digital modulation technique
disadvantage-
1.since amplitude keeps varying so there is noise associated with it.
2.due to nyquist criteria its require high bandwidth.
3.due to amplitude variation peek power of receiver also varies with it
nitesh
What are branches under electronics and communication engineering?
Electronics and Telecommunication is the mother branch of IT. This branch is having wide scope in the public sector, Private sector as well as in Government sector.
What can you say to charging and discharging capacitor?
A capacitor will charge at a set time of 63% for one time constant and will continue to do so until fully charged which mathematically will never happen. therefore in the industry a 5 time interval is considered as fully charged.
A capacitor whose capacitance is variable (within some range). They are usually used to adjust resonant circuits or delay circuits.
Is active is a cutoff region of transistor?
The active region of a transistor is when the transistor has sufficient base current to turn the transistor on and for a larger current to flow from emitter to collector. This is the region where the transistor is on and fully operating.
Which DC motor is constant speed motor?
Dc shunt motor is constant speed motor.Its speed is constant with armature current.This shunt motor is used in paper mills and drilling machines
What is potential barrier in PN junction?
Whenever two dissimilar conductors touch a "potential barrier" forms. All conductive materials have a voltage above zero that an electron must have to enter the material. In true conductors, this voltage is very low. In semiconductors, it can vary, but is usually in the 0.25 to 6.8 Volt range. In insulators, it can be very, very high. When two semiconductors or a metal and a semiconductor touch the difference is polarity sensitive. The higher the "band gap", the voltage that must be overcome to enter the "conduction band", the higher the voltage drop in the forward bias direction. Think of the "band gap", or potential barrier, as being like a curb on a road and sidewalk. It's easy to ride a bike off the sidewalk over the curb onto the road, but not so easy the other way.
In modern electronic multimeter a fet or mosfet is preferred over bjt because?
Because of its much higher input impedance. When measuring voltage,
that makes the voltmeter appear to the circuit as if it's not there, so
the presence of the voltmeter doesn't change the operation of the circuit.