Electronics Engineering

you would induce voltage therefore chanfing the magnetic field

What kind of wound mechine is this...if it is wave wound mechine than Eg:357

The reason for the total voltage drops across the capacitance and inductance IN AN AC CIRCUIT has to do with the different phase angles of the voltages.

First, current is the same value and same phase angle everywhere in a series circuit. But, voltage across a capacitor lags current by 90 degrees (capacitor current leads voltage). Next, voltage across a pure inductance leads current by 90 degrees (inductor current lags voltage).

The rule that all voltages in a series circuit have to add to the supply voltage still applies, but in this case, the voltage drops are added VECTORALLY, not arithmetically. If you were to graph this addition, you would show any resistance voltage in phase with the current, the capacitor voltage at -90 degrees to the current and the inductor voltage at +90 degrees to the current, for a phase difference between them of 180 degrees, cancelling each other out.

In a series resonant circuit, the impedances of the capacitor and inductor cancel each other. The only impedance to the flow of current is any resistance in the circuit. Since real-life inductors always have some resistance, at least there is always some resistance in a series resonant circuit.

Detecting and ranging (measuring the distance of) enemy craft in air (planes) and water (ships and subs).

The 7474 is one of a set of Integrated Circuits in the 7400 family. It is a microchip that acts like a switch. It has 1 byte of memory to remember the status when it was last triggered. The "Dual Flip Flop" means there are two of these identical "switches" contained in the chip package. More modern variations of this unit are seen in many electronic devices, especially robotics.

If the question means to indicate multiplication, then the product is 75,000 cubic ohms.

This quantity has no physical meaning or significance.

The output of the common emitter amplifier is inverted because increasing the base-emitter current causes a proportional increase in collector-emitter current. That increase in collector-emitter current pulls the collector towards the emitter, so the voltage on the collector will go down when the biased base voltage goes up, and vice versa. This is the characteristic of the Class A Common Emitter amplifier.

Responding to a request for more details...

This is for the NPN transistor. It applies to the PNP transistor as well, but directionality of voltage and current increases is reversed in that case.

Start with the base-emitter circuit. You have some kind of bias network holding the base at a certain voltage. That voltage represents a certain current, which goes through the base-emitter junction and emitter resistor, if there is one. Typically, you consider that the emitter voltage is less than the base voltage by the amount of one diode junction, or about 0.7 volts. If you were to increase the input voltage, you would cause a corresponding increase in base-emitter current.

The transistor has gain, beta-dc or hFe, which is basically the ratio of collector-emitter current over base-emitter current, so the base-emitter current is controlling a larger collector-emitter current.

Now, focus on the collector-emitter circuit. You have some kind of resistor in the collector, and you might have some kind of resistor in the emitter. (More on the emitter resistor later.) Think of this circuit as three resistors in series, the collector resistor, the equivalent resistance of the collector-emitter junctions, and the emitter resistor. This also represents a current, one that is being controlled by the base-emitter resistance.

Note that the base-emitter current is being added to the collector-emitter current, so the emitter current, by Kirchoff's current law, is the sum of the base and collector currents. Since the gain is relatively high, however, the contribution from the base is generally negligible. (In high power transistor amplifiers, gain is usually low, so base current is not negligible, so we do take it into account.)

The crucial factor here is that the collector current is proportional to the base current, in the ratio of beta-dc, or hFe. If, for instance, base current were increased by 1 ma, with an hFe of 200, then the collector current would increase by 200 ma.

Well, sort of....

You have to consider the transistor's limits, and you have to consider whether or not you are opereating in linear mode. Limits are easy, just check the specs. Lets look at linear mode...

If you attempt to pull more collector current than the collector-emitter circuit would allow, i.e. to make the equivalant collector-emitter resistance go to zero, then the transistor starts operating in saturated mode. In saturated mode, the transistor is acting as a switch, and it is distinctly non-linear. Even if not saturated, the transistor can be poorly linear when operating at the ends of the linear range.

This is why any good design includes consideration of linear mode range. You want to operate in the center of the linear range, which simply means that we bias the base to cause the collector to be in the middle of its optimal range, giving maximum linearity.

Summarizing so far, we have a transistor that is multiplying its base current by some factor, beta-dc or hFe, causing a proportional collector current. With this viewpoint, the amplifier is non-inverting because increasing base current causes collector current to increase.

We call the circuit inverting, however, because we want to think of the collector voltage rather than the collector current.

Remember that the transistor has an equivalent resistance. In particular, the collector-emitter resistance changes in response to stimuli on the base. In order for the collector current to increase, the equivalent resistance must decrease.

Looking at the collector-emitter circuit, you have a voltage divider, collector resistance at the top, and the sum of equivalent collector-emitter resistance and the emitter resistance at the bottom. It is easy to see that, if the collector current increases, the collector voltage must decrease. That is why we call this an inverting amplifer.

Back to the emitter resistor...

When we say "common emitter", we mean that the emitter is common and we analyze everything else. You can design and operate this amplifer with no emitter resistor, and that would be a true common (or grounded) emitter configuration. Problem is the circuit will not be stable...

First, gain varies amongst transistors, even amongst transistors of identical design. It is common to state that hFe ranges from 80 to 400, as an example. The circuit design must consider this variability. If you want predictable and stable gain, you must compensate for gain variation. You design the circuit for minimum hFe, but you look at what happens with maximum hFe.

To make matters worse, the junction voltage at any particular current varies with temperature, sometimes substantially. This means that your beautifully designed circuit is unpredictable when it gets warm, and all circuits that manipulate power, even small amounts of power, get warm. Its all a matter of degree.

There are many ways to compensate for gain variations. One of them is to use an emitter resistor. This effectively places a limit on gain by moving the primary factor for gain from the transistor to the circuit.

The gain of a common emitter amplifier is hFe. When there is an emitter resistor, however, the gain is collector resistance divided by emitter resistance. If that ratio is less than hFe, then hFe variability will not affect gain.

whether we know that p-n diode is real diode. But still in case of semeconductor we see then silics is real diode.

A y chart is drawn on a paper dividing the paper into three by drawing a y to divide it.

It is used by brainstorming.

for psu exam u should have minimum 65% marks in your engg carrier.

With straight electronics, one way to design a multiplier circuit would be with an operational transconductance amplifier, such as the CA3080, with one input driving the input pin and the other driving the gain control pin. This can be biased and calibrated to perform multiplication. Another way is to use a four quadrant multiplier chip, such as the AD834, which is based on transconductance as well, but designed specifically for multiplication. With a microcontroller, a better solution in low frequency applications, you can read the two inputs with two analog to digital converter inputs, multiply those values in software (applying whatever offset and calibration desired) and send the output to an digital converter output.

I know that it is 120W "RMS" (which I've been told that is an erroneous term) but there is another kind of watt. I don't know how it is called. The kind that stereos use in stores.

Port 0 is called true bidirectional port..............

swapneel

Thyristor is a kind fast acting switch. These are fully controlled switches

features of an expert system are: explanation facility, easy modification, transportability, and adaptive learning ability

Natural bandwidth refers to the range of frequencies over which a system can operate effectively without significant distortion or loss of signal integrity. In communication systems, it indicates the frequency range that allows for optimal transmission of information. The concept is often applied in various fields, including audio engineering and telecommunications, to describe the limits within which a system can accurately process or transmit signals.

A key fundamental difference in the practical use of the terms is under what authority the operations are conducted - Title 10 or Title 50.

Electronic Support Measurement (ESM) is the interception and processing of RF signals in support of tactical military operations, rather than for intelligence collection purposes. For example, the AWACS ESM system executes RF interception and signal processing to provide AWACS and other systems with a current picture of the Electronic Order of Battle (who's transmitting what kind of signals from where, what does the RF picture mean, and what can we do about it - e.g., setting the right parameters for Electronic Countermeasures or jamming).

ELINT (Electronic Intelligence) is the interception and processing of RF signals for the purpose of gathering intelligence, either tactical or strategic. The charter for ELINT collection is in the Intelligence Community (IC); when military units do ELINT, they are executing as a Service Cryptologic Component (SCC) using delegated authority from the appropriate chartered IC element.

Different organizations in the US DoD use custom modifiers to better define what they mean by ELINT. "Technical ELINT" is ELINT that seeks to obtain fine detail in the measurement of signal parameters; "Tactical ELINT" is ELINT that provides intelligence in direct support of the tactical warfighter mission.

With modern technology, the requirements for sensors and processors to effectively execute the ESM and ELINT missions have converged. Also, warfighter needs and resource limitations are driving ELINT systems to support near real-time needs of the tactical warfighter. As the capabilities of the systems converge, only one real difference remains between ESM and ELINT: ESM missions can be done by the military warfighters under their own Title 10 authority, while ELINT missions need to be done under TItle 50 through SCC delegation from the IC.

No India uses 240V at 50Hz the U.S. uses 110V at 60Hz.

offcourse, there is scope in nhpc

la lg ah.basta mu na sa! anu cmu haw?

U= RxI U/I=R 3/1=3 P=UxI So you need a 3 Ohm resistor that can take at least 3 Watts

it is the disturbance between equipments and its productions.

The effective resistance between opposite corners of a cube comprised of twelve 6 ohm resistors, one at each edge, is 5 ohms. There are several ways to solve this. One approach is to build a system of 12 equations in 12 unknowns, and solve them. Another approach is this... Consider that there are three resistors leaving the input node, and there are three resistors entering the output node. In between those three resistors, there are six resistors in a criss-cross matrix. (Draw it out, flattened, to see this.)Inspecting the six resistors in the center, you note that they are completely symmetrical. Since they are symmetrical, you can conclude that the voltage at the junction between the three input resistors and the six others is the same voltage. The same goes for the three output resistors. Said another way, the voltage across the three input resistors and the three output resistors is the same. Given two or more nodes in a circuit having the same voltage, you can draw a wire connecting them, i.e. a resistor of zero ohms. This does not change the characteristics of the circuit in any way, because zero voltage across any resistance is still zero amperes. Now that you have made these connections, look at the circuit. It has simplified to three parallel resistors, in series with six parallel resistors, in series with three parallel resistors. Three 6 ohm resistors in parallel is 2 ohms. Six 6 ohm resistors in parallel is 1 ohm. Three more 6 ohm resistors in parallel is 2 ohms. The total resistance is 2 + 1 + 2 ohms, or 5 ohms.

No. Transformers work in AC systems, not in DC systems.

To reduce DC voltage with a zener diode you place a resistor in series with the zener and setup for the reverse bias condition. You pick the resistor to bias the zener at the desired reverse current. You also have to consider the load across the resistor, across the zener, and across the target load. Often, this configuration is used to establish a reference voltage for something else, such as an op-amp controlled emitter-follower, but it is possible to use just the resistor and zener if you consider all the factors.