0
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
What is a -3dB point in an inverting amplifier?
The -3dB point is the point of half power. In a filter, the -3dB point, more commonly called the half-power point, is the point where the output power is one half the input power. A bandpass filter has two half-power points, and the distance between them is called the bandwidth, whereas a low-pass or high-pass filter has one half-power point, which is called the cutoff frequency. In terms of voltage, the half-power point is where the voltage is 0.707 (1 / square root(2)) of the input voltage.
A: The power company must have trouble at the switch-yard to do that like a short or extreme loading. If there is a fault power management will know immediately because snitches will open and stay open. the operator will manually energize those switches 3 times to see if the fault can be cleared if not a crew will be sent to fix the problem. Sometimes some testing is necessary to find the problem so be patient time with no power means a lot of lost revenues mega $$
Why use blocking diode across the relay coil?
Coils have the strange property that when electricity is released from them, they reverse polarity and spike the remaining current back towards the source.
The diode is there to "block" this from hitting the power supply and potentially causing damage.
V = ir
v = (0.5)(250)
v = 125
In digital electronics Race-around condition is not present in?
A race condition is an undesirable situation that occurs
when a device or system attempts to perform two or more
operations at the same time, but because of the nature of
the device or system, the operations must be done in the
proper sequence in order to be done correctly.
In computer memory or storage, a race condition may occur
if commands to read and write a large amount of data are
received at almost the same instant, and the machine
attempts to overwrite some or all of the old data while
that old data is still being read. The result may be one or
more of the following: a computer crash, an "illegal
operation," notification and shutdown of the program,
errors reading the old data, or errors writing the new
data. This can be prevented by serialization of memory or
storage access, such that if read and write commands are
received close together, the read command is executed and
completed first, by default.
In a network, a race condition may occur if two users
attempt to access an available channel at the same instant,
and neither computer receives notification that the channel
is occupied before the system grants access. Statistically,
this sort of coincidence is most likely to occur in
networks having long lag times, such as those that use
geostationary satellites. To prevent such a race condition
from developing, a priority scheme must be devised. For
example, the subscriber whose username begins with the
earlier letter of the alphabet (or the lower numeral) may
get priority by default when two subscribers attempt to
access the system within a prescribed increment of time.
Hackers can take advantage of race-condition
vulnerabilities to gain unauthorized access to networks.
Race conditions occasionally occur in logic gates when
certain inputs come into conflict. Because the gate output
state takes a finite, nonzero amount of time to react to
any change in input states, sensitive circuits or devices
following the gate may be fooled by the state of the
output, and thereby caused to not operate properly.
source : http://www.allinterview.com/showanswers/10617.html
Why should a technician that is working with a computers hardware wear an anti-static wrist strap?
the wrist strap will prevent computer components from being damaged by static electricity.
How crystal oscillator provides good frequency stability?
A: It is a mechanical device once it is exited it will oscillate at its mechanical frequency unless the mechanics changes it will not drift as compered to other oscillators
Should a Voltmeter always be connected in a series with a component?
Voltmeter should be connected always in parallel to a circuit
ANSWER : IT should be in parallel except when used to measure current. Then it should be placed in series across a shunt.
Are no load and short circuit similar?
No. No load and short circuit is not similar.
No load can be 1) Either open circuit i.e. Only Potential is available and load is not connected 2) Load (i.e. motor etc ) is connected but not working with full load or full capacity. In this case the current will flow through the circuit depending on the load. It means No load condition is a condition where no current or a small ( relative / comparative term) current is flowing through the circuit.
In Short circuit the load side resistance/ impedance become so less that very high amount of current is passing through circuit.( The protection is therefor required for any circuit)
No load and and short circuit is not similar.
Thanks
What is the cost for an AC to DC power converter?
The cost for an AC to DC power converter is usually around $15-$20. You can purchase an AC to DC Power converter online at the Amazon website. Once on the page, type "AC to DC Power Converter" into the search field at the top of the page and press enter to bring up the products.
Why is gap voltage is negative in Bently Nevada vibration monitoring?
Years back.. That guy who invented that had no money but to buy cheap electronics... Later he had no reason to change it so they kept it!
Why can't the potential barrier of a diode be used as a voltage source?
The potential barrier of a diode is caused by the movement of electrons to create holes. The electrons and holes create a potential barrier, but as this voltage will not supply current, it cannot be used as a voltage source.
What is latch in microprocessor?
Latch are just like inputs which are used to set or reset the output for a given combination.
Why does a phase shift occur in a ce transistor?
In any transistor circuit , there is a phase shift. It takes a finite time for the controlling signal, usually on the base connection, to have an effect on the circuit and cause a change to the output. The shape of the signal remains but it is shifted in time (phase). The difference varies by configuration. It can be as much as180 degrees if the circuit is inverting the signal. The addition of passive components add to the shift.
To make a chip and implement it with a software program, you need to "burn" the program into the chip before it can work. You must use special chips, called programmable read only memory chips, commonly called PROMs, for this. It also requires special machinery to program the chips.
Why does the Fermi energy level lie closer to the conduction band than the valence band?
Fermi energy levels can be anywhere. Anywhere. But can an electron actually be in a given energy level? There are specific Fermi energy levels associated with each atom where electrons might "hang out" or orbit. Certainly each electron in the atom occupies a given Fermi energy level. There are other Fermi energy levels where the electrons will go if they are given energy to go there. And there are yet other Fermi energy levels where the electron simply cannot be made to go because of quantum mechanical principles. That's in a single atom. There are other Fermi levels that electrons might occupy associated with collections of atoms that did not exist with just a single atom. Said another way, collections of atoms that make up a material cause other Fermi levels that didn't exist before (in the case of a single atom) to become possible places for electrons to be in the collection of atoms that is the material itself. In materials, the valence band is "here" and the conduction band is "here" and they either overlap (in conductive materials) or they don't. In insulators, the conduction band is above the valence band of the atoms and other bands that might be possible because of the macroatomic structure of the material. If the two bands do not overlap, then there is a band gap. The band gap is a "forbidden region" for electrons. They cannot exist there because the quantum mechanical properties of the electrons and the atoms of the material won't sustain their presence in that group of Fermi energy levels that make up the band gap. The question asks why the Fermi energy level lies closer to the conduction band than the valence band. Hopefully the information provided illuminates the situation and shows that Fermi energy levels don't lie closer to the conduction band than the valence band because Fermi energy levels can be anywhere. There is also the question of whether an electron can actually be allowed to be in a given Fermi energy level. Lastly, it's also a question of whether or not the conduction band is "low enough" that it overlaps the valence band where the valence electrons are hanging out.
C = 9600 = 2B*3 = 2B * 3 W = 1600 Hz
What is a voltage time base generator?
I believe you are referring to a piece of test equipment also known as a "function generator." It generates a voltage equal to some function of time. The most basic models will produce sine, square, and sawtooth waves at different frequencies, but the more expensive models will do all kinds of waves. these voltage time base generators are those which are used to generate voltage linearly with time. by using the transistor as a switch and using a capacitor we can get the ramp out put. here the working would be the capacitor charging when the transistor is off and discharging when the transistor is on. the discharging time is very less compared to the charging time. when the capacitor charges voltage across it increases exponentially and we get a wave which increases linearly with time.
