Electrical Engineering

There is no single answer here, since the power factor varies with, and is a function of the load. A bunch of electric motors will have a very different PF than, say, a room full of computer servers. If the load is unknown, a rule of thumb is to use 0.85 (85%), but this would be no more than a guess.

it stands for Variable Frequency Drive. It uses either a local controller or an input signal to control the frequency or speed of a motor.

You just stated that the voltage across the resistor is 15 volts, so that's your answer !

If the resistor is connected to a 15-V battery or to the output of a 15-V power supply, then a meter across the resistor is also across the power supply, and reads 15 volts.

The current through the resistor is (V/R) = (15/2700) = 5.56 mA. The power dissipated by the resistor (and delivered by the battery) is (V2/R) = (225/2700) = 0.083 watt.

As a range is a high current device, the electrical code stipulates that it has to have its own breaker. The breaker protects the wire feeder. An electric range breaker is set to trip at 40 amps. Using a smaller wire that #8 is not allowed as their ratings are below that of the #8 wire. #10 wire rating is 30 amps, #12 wire rating is 20 amps, and #14 wire rating is 15 amps.

f=1/T so f = 1/.025 =40Hz

Assuming you are talking about an AC circuit, then the total opposition to the flow of current in an R-C circuit is called its impedance (symbol: Z), measured in ohms. This is the vector sum of the circuit's resistance (R) and its capacitive reactance (XC) -each also measured in ohms.

If you are referring to a 'fruit cell' then, in common with all cells, the voltage is determined by the materials from which the electrodes are made -not by the fruit itself. The further apart the metals are on the 'electrochemical series' of elements, the higher the resulting voltage -so, for copper and zinc, the voltage will be about 1.1 V.

Large a.c. currents with a small trigger signal.

You must use thermocouple wire (of the same type as the thermocouple) to extend the circuit. If you switch to a different wire the point of connection between the two becomes a thermocouple junction itself, and the resulting voltage from that junction will skew your reading.

You can use any wire to extend a thermocouple connection if you know the temperature of the junction where the thermocouple wire ends--this becomes the reference junction.

Here is the formula,

Per hour consumption = Diesel consumed / Total DG run hours

Diesel consumed = Previous closing balance - Actual closing balace

Daily DG run hours = (Total DG run hours / (DG capacity*24 - Total DG run hours)) * 24 / (( Total DG run hours / ( DG capacity * 24 - Total DG run hours )) + 1

Regards,

Shibin

shibin.hesel@gmail.com

Most likely, yes. The ultimate test is if it can be pushed in either direction and it stays running in that direction.

what is magnetic ppermeability of EN8

If you have an automobile, you may be aware of the cost of gasoline. If not, you have seen automobile owners purchase gasoline. If you drive down the highway, the automobile uses gasoline. The car engine uses gasoline for a source of energy to make the car move. The engine makes the wheels move.

As the wheels move they produce rolling friction. The engine must overcome this rolling friction. The weight of the engine and transmission on the wheels adds to this rolling friction. If a way could be found to remove the engine and transmission from the car, the rolling friction could be greatly reduced. Maybe instead of having the engine as part of the car, we can place it between two tracks. We will make it magnetic. We will try that.

While we are at it, maybe we can reduce the rolling friction all together. Maybe we can use the repulsive force of magnets to hold our vehicle a millimeter or two above a track. That would do away completely with rolling friction. Yes, We will have the motor a long strung out electric motor between the tracks and we will not need wheels to drive the vehicle. Then we can levitate the vehicle a few millimeters above the track. What do you say we call it a maglev train. Once we get out the kinks, it will be a lot less expensive to run than current equipment.

Such trains will not be built any time soon in the United States except for short distances. Current train tracks simply are not straight enough. The distance between standard gage tracks can vary in width by 1/2 inch. That is far too much for a maglev train. It would be necessary to secure new right of way.

Lets put a value to the transformer, say 500 VA. Step down with a 5:1 ratio. Say 250 volts on primary. 250/5 = 50 volts secondary. 500 VA transformer/50 volts secondary = 10 Amps. Therefore the secondary would have to have the larger wire to accommodate the larger current.

When I consider both cost of cells, and how soon they must be replaced, the clear looser is the Super Heavy Duty also-known-as Carbon Zinc. The only reason to buy them is when you want to thwart thieves from stealing more desirable cells.

In an intrinsic semiconductor, a few electrons get thermally excited and break from their valence bond to become a free electron. This leaves behind a vacancy in its place called 'hole'.

In a P-type semiconductor, B with 3 electrons replaces a Si atom with 4 electrons in the lattice. 3 covalent bonds are formed by B with 3 neighbouring Si. But there is a deficiency of one electron in B for bonding with the 4th Si. This deficiency/vacancy is called a hole.

When an electric potential difference is present, the electrons from adjacent valence bond moves into the vacancy near it while moving along the potential.

The following represents the movement of valence electron.

Terminology:

* represents valence electron

_ represents hole

A is -ve and B is +ve.

..I A * * * _ * * * B

.II A * * _ * * * * B

III A * _ * * * * * B

.IV A _ * * * * * * B

I- Hole is at the 4th position.

II- At first, the 3rd electron from left shifts right to fill the vacancy and leaves behind a vacancy in its place. The vacancy is at the 3rd position.

III- Next, the 2nd electron from left has shifted to the 3rd place and filled up that vacancy but leaves a vacancy at its place. The vacancy is at 2nd position.

IV- Now, the 1st electron from left moves to occupy the vacancy at the 2nd position creating another vacancy in its own place. The vacancy is at 1st position.

As the electrons moved right, the vacancy moved left. The vacancy is called a hole (just a shorter name for convenience). The movement of holes is really the movement of electron in the valence band. Therefore, the mobility of a hole is indirectly the mobility of valence electrons.

Mobility is the velocity acquired per unit electric field.

In the intrinsic and N type semiconductors, many free electrons are present i.e. electrons in conduction band which are free to move in the crystal as against valence electrons which can only move in the lattice points.

When an electric field is applied, both the valence electrons and the free electrons move in the same direction. The hole direction is opposite to that of valence electron but the mobility is the same, as explained earlier.

Even for the same electric field, valence electrons cannot move as freely as the free electrons because its movement is restricted. Therefore, the velocity of valence electrons is less compared to free electrons. In other words, the velocity of holes is less compared to free electrons. This means mobility is also less for a hole compared to free electron.

Thus, mobility of a free-electron (often abbreviated as 'electron') is greater than that of a hole (indirectly referring to valence electron).

Actuators are used for the automation of industrial valves and can be found in all kinds of technical process plants: they are used in wastewater treatment plants, power plants and even refineries. This is where they play a major part in automating process control. The valves to be automated vary both in design and dimension. The diameters of the valves range from a few inches to a few metres.

Use the link below to see some pictures rather than sit through a description. Click and find out firsthand if a picture is worth a thousand words.

OK, here is your problem. Firstly, you spelt the question wrong. Secondly, i Dont know.

what is the fault in the transformer, it trips when it is charged.it is charged through the 100 amps MCCB.

If you're talking about NDI or NDT, radiography is a much longer process (developing film etc.) and a more tedious task than UT. You have to operate in a dark room, set up the x-ray tubehead.. etc. Also, radiography has a lot more risks than UT.

It stands for kilo or 1000 ohms.

No, Agapito Flores did not invent the fluorescent lamp but it is true that there is a very popular myth in the Philippines that he did do so!

Agapito Flores was not recognised by the mainstream scientific community.