Electronics Engineering

it will improve the power factor... The angle between voltage and current will decrease depends on capacitor value.

A clock is an instrument used to indicate, keep, and co-ordinate time.

1 gate.

LCDs are driven with AC, to prevent electrolytic damage to the thin transparent electrodes. LEDs are driven with DC.

Yes, some could be used for analog monochrome TV but lots of extra circuits would be needed. Picture would be green. Cost of oscilloscope would likely be several times a portable analog TV of similar size, even before adding extra circuits.

Both radial and axial forces.

A diode will only conduct electricity if the polarity of the current is in the correct direction, because diodes can only conduct in one direction.

Yes. That is what microphones do.

A grid DC tie is where AC is converted into DC, which is then converted to AC again on the other side. If you have a DC to AC transformer setup, you'd need to add a second one going the "other" way for a full DC tie station.

usually symbolized by series of short and long lines (looks a lot like the "justify center" symbol in word processors). A voltage source in the real world can be anything that causes an electrical imbalance between two physical points that wires can be connected to. We made a battery out of potatoes in science class once, we buy batteries in stores, solar panels are used more commonly in the little yard lights, wall outlets are AC voltage sources, high voltage power lines build up electromagnetic fields that induce currents in metals next to them, wind and tides push turbine blades that turn generators, Van De Graff generators are transient voltage sources, etc.

Neither of these terms is normally applied to a transformer. You may be thinking of a 'mutual tranformer' and an 'autotransformer'. If so, then a 'mutual transformer' is a transformer which has electrically-isolated primary and secondary windings, whereas an 'autotranformer' (the term, 'auto', is misleading and has nothing to do with the transformer being 'automatic'!) has a common and series winding, meaning that the primary and secondary sides are electrically connected to each other.

the process of converting iron to a permanent magnet is called magnetization.

As iron is a ferro magnetic material it is magnetized by applying strong magnetic field across it , this makes the alignment of all the magnetic dipoles present in iron in the same direction .Even after the external magnetic field is removed they retain their arrangement , thus it becomes a permanent magnet

Rom :-

Read Only Memory. The storage of data and instructions in Rom is permanent. It does not depend on the power supply. The memory which does not lose its content when power is turned off is known as non-volatile memory.

There are three types of Rom :-

Prom = Programmable read only memory

Eprom= Erasable Prom

EEprom=Electrically erasable prom

An 8051 is unlike most modern processors in that the ports are essentially open-collector drivers. Some of the ports (1, 2, and 3) have internal pull-ups, but these are usually quite weak (500 micro-amps or less); port 0 has no pull-ups at all. When the chip is reset, 1s are stored in all port bits. When a 0 is written to a port pin, it is pulled down to ground, with a current rating that varies widely depending upon the specific variant. The original Intel 8051H could only sink about 7 mA (4 TTL loads), but most chips now will sink 15-20 with no problems - enough to light an LED.

Another way of thinking about this is that, upon reset, the port pins are all 1s. Because of the weak or no pull-ups, they can be used as inputs. The only output state for a port is low, so if an external load needs to be driven, it must be a "sinking" type of load.

A current transformer (CT) is used to reduce a load current to a value that can be read by conventional instruments such as ammeters and wattmeters; it also enables the instruments to be located remotely. In the case of high-voltage circuits, a CT also electrically-isolates its burden (secondary load) from the primary circuit.

the binary semiconductors used to make LEDs have forward bias voltages from 1.5V to 6V depending on color (1.5V for IR-red to 6V for blue-UV) because the bandgap voltage of the semiconductor is higher than silicon. This higher bandgap is where the photons generated get their energy from.

germanium has a lower forward bias voltage of 0.2V because the bandgap voltage is lower.

metal-semiconductor contacts, like point contact diodes and schottky barrier diodes, can have forward bias voltages under 0.1V

stores charges

Because in ECL logic Transistors doesn't go to saturation region hence saving the recovery time and making this family the faster.

In the general sense of the question one can in a general term say that where it applies to output drives, that it improves the control the drive have over the actuator it controls and in other applications it "might" improve energy efficiency and output stability depending on the application and available options.

Just to establish an understanding to the general theory that might assist in a wider range of applications. The load impedance is the impedances seen from the source, the output impedance is the impedance seen from the load. All what this means is that, if the load would have acted as a source of energy, the output impedance is the load impedance the drive circuit will impose on such source.

In my experience in electronics, this is best demonstrated in the field of high fidelity audio power amplifiers. The reason I mention high fidelity is because even for most general purpose power amplifier application for all practical purpose it is just not that important.

The amplifier has the function to provide energy to the loudspeaker where the loudspeaker will respond to that electrical energy by converting it to mechanical energy. In the process the loudspeaker has many mechanical characteristics that influence its behaviour. Some of these characteristics might be due to the weight of the cone, voice coil or the elasticity of the suspension components. This however leads to the actual behaviour of the loud speaker to deviate from the control signal (audio) resulting in unwanted audio characteristics where the most prominent one in this context is known as a damping factor.

Damping can be demonstrated in simple terms by securing the tip of a ruler the edge of a table, the mechanical nature of the structure will cause it to continue to oscillate for a while after you gave the other free hanging tip a slight knock. The oscillation will gradually loose momentum and discharge its mechanical energy into the surrounding structure and so on. This happens to a practical loudspeaker as well after an electric pulse is introduced to its voice-coil, it will continue to oscillate for a short period of time after each change in state. But, as this voice-coil continues to oscillate through the magnetic pole-ring it will generate electrical energy that is effectively fed back to the amplifier. The output impedance of the amplifier will act as a load to this energy being generated by the voice-coil. If the amplifier has a low output impedance, then it will become more difficult for this voice coil to freely move as the current caused by the low output impedance will setup a magnetic force that apposes its direction of movement resulting in the position of the voice-coil to be better secured to the status of the control signal.

This however leads to the fact that the lower the output impedance of an amplifier is, the more control the amplifier has to the absolute movement, rate of change and position of the voice-coil resulting in more precise audio reproduction. However some manufactures claim ridiculously high damping factor for high fidelity audio amplifiers. This however have little use to even the audiophiles as the resistance of the voice-coil as well as the loud speaker cable resistance will limit the positive effect of the damping factor has beyond the approximate factor of 50. The damping factor is purely the ratio between source resistance and load resistance and therefore (loudspeaker +cable) impedance divided by output impedance is the damping factor. Just to reiterate that high damping factor is a direct result of low output impedance and therefore to keep the output impedance low is a good thing, but at some point one must bare in mind that the design for low output impedance should not go overboard for the application it applies too. One must bare in mind the load resistance ext.

In some cases an application might enjoy the advantages of other specifications and therefore design considerations should never only value output impedance. For example Class B amplifiers are capable of excellent low output impedances while they are known for poor energy efficiency in comparison of Class D amplifiers which are more energy efficient, and often better precision at low cost, But they lack that nice low output Independence. Where a portable music center might benefit from the Class D amplifier for practical reasons, a top-end high fidelity system might prefer the Class B amplifier, slightly modified, for its simplistic first principal operation and low output impedance that will result in an excellent damping factor on the conditions that the correct loudspeakers and cables are used.

As with audio there may be other applications in industry and science where low output impedance for much the same reasons will be a design requirement in precision control of actuators. In high power applications even more critical to ensure proper supply or prevention of unnecessary internal energy losses or heating. However some application considerations need to be scrutinized where the demand for low output impedance becomes unreasonable. As many factors such as cabling, temperature and many uncontrollable factors can result in deviations and unrealistic expectations and therefore, must enjoy a fair consideration.

Uh dun't nuh

because +feedback amplify noise also.it amplify the noise to input ratio by[1/(1-G.H)].

WHERE g=open loop gain

H=feedback gain

because without using capacitor or resistor in a circuit,it cant be complete.Resistor is used to protect the circuit by giving a certain amount of voltage.Capacitor is used to charge and discharge purpose.

Probably you are referring to an Exlusive OR gate (XOR). This logic function (also implemented as an electronic circuit) outputs TRUE (or high) when one and only one of its two inputs is TRUE (or high). A regular OR gate outputs TRUE when either or both of its inputs are TRUE.

Open circuit has no current, so does that mean any resistor in series with it, has no current ,so it can be ignored for analysis( v=ir so 0 current means 0 V) for finding lets say the Thevenin equivalent.?

Now for Short circuit, do we ignore a resistor in series with the short, because current will take path of least resistance and ignore that resistor?

Also can short circuit have voltage through it ?