Electrical Engineering

Sure. No transformer is built to last forever. Aging and operations will weaken the insulation with time.

if i remember correctlly it was Benjiman Franklin, or he was the one who discovered AC..

it's some one at that sentury..that is all i know... lol..

yes if you happen to look at them during blow up. the worst offenders are tantalum whereby they unwind in a long stream of metal

If it's burnt out it has to be replaced! - I'm sure someone could repair it but it would be 10 times the cost of buying a new one.

yes

Power dissipated by the resistor = I^2 * R or V^2 / R, where R = its resistance value, I = the current in the resistor, and V = the voltage drop across the two terminals of the resistor. You need to measure or find the information of either I (using an ammeter) or V (a voltmeter).

The Drift Speed is less than the average speed of the electron between two collisions. Electrons move relatively slowly along a wire but very quickly between collisions. The electric field (EMF) that causes the motion moves at the speed of light.

1 kW = 1000 w

So 500 W / 1000 W = 0.5 kW

As soon at the heater is turned on, it starts to use energy at the rate of 500 W = 0.5 kW.

If you leave it on for 10 hours it will have used up 0.5 x 10 = 5 kWh

That is a sound pressure level meter (SPL meter).

conductivity of semiconductors increases with increase in temperature as breakdown of covalent bonds take place in the semiconductor due to increase in temp but more & more increase in the temp may result in the breakdown or damage of the semiconductor which results in the decrease in conductivity of semiconductor

--transformer which is liquid cooled..

--normally used to couple telephone and electronic equipments.

--care should be taken to maintain this type.

-- fire proof vault is normally needed(b'coz it's using oil (mostly) for cooling).

Civil engineering deals with civil construction, structural design, buildings, roads, bridges etc

Transformers are used to step up or step down electricity as it moves from the point of generation to the point of consumption.

One who responsible in monitoring of equipments interlocked to bms system.

AISC stands for application specific integrated circuit. it's function is determined during it's design and manufacture, it is not programmed.

why we call pf other name UIK,

It will make more sense if you first study the construction of MOSFET. It has three terminals, Gate (G), Source (S), and Drain (D). G is insulated from the S and D. Between S and D is a variable resistor, whose resistance depends on the voltage applied across G and S. Since SD is basically a resistor, you have power dissipation when a voltage is applied across S and D. Power dissipation = Vds * Ids.

For telecom engineers, it is very help full to know about MAIO. Basically there is a set of frequencies where the channels are hop to avoid interference that set of frequencies is called MA-LIST. suppose MALIST contained frequencies [A,B,C,D,E,F,G,H,I,J,K,L].
Then MAIO corresponds the starting point of hopping sequence. suppose there are four TRx in one sector. then MAIO will be, for example, 0,2,4.
for first TRx for traffic, the MAIO is 0. means that hopping sequence starts from first frequency in the MALIST, that is frequency A. and for MAIO 2 it starts from frequency C and for MAIO 4 it starts from frequency E.

Also HSN (hopping sequence number), ranges from 0 to 63 . if we use HSN as, for example 4 it means that for MAIO 0, the sequence starts from frequency A and repeats frequencies in following manner.

For MAIO 0 and HSN 4
A,F,K,D,I,B,G,L,E,J,C,H,A,F

For MAIO 2 and HSN 4
C,H,A,F,K,D,I,B,G,L,E,J,C,H

For MAIO 4 and HSN 4
E,J,C,H,A,F,K,D,I,B,G,L,E,J

Voltage drop is caused by resistance. From the equation V=IR the voltage across that resistance can be calculated. For a uniform conductor the resistance is linear with the length R=kx where k is in ohms per foot. For a given current, the voltage drop V=Ikx so the voltage drop per foot is Ik. Voltage drop per foot can be measured, allowing a calculation of voltage drop for very long lengths of conductor such as power transmission lines. This is a reasonable approximation as long as the total voltage drop in transmission is small relative to the supply voltage. If the voltage drop is large, the current will be limited by the total resistance. This implies that long distance transmission lines should be high voltage, because 1 megawatt at 10,000 volts requires 100 amps, while at 100,000 volts it only requires 10 amps. The voltage drop per foot for the same conductor would be 10 times as large at 10 times the current, and the power loss (I*IR) would be 100 times as large.

For alternating current, inductance can be a factor; this implies that relatively low frequency would be preferred.

it does so...as because of commutation process.

bcoz......in dc current we cant avoid sparking and hence it uses ac supply....

so that i changes its direction in up nd down motion just like a sine wave..so commutation procees occurs..and it avoids sparking..........

hence ac is preferd

no such things..trust me

Back to back testing of a transformer can be better explained if you check the diagram in the resource area.

inrush uses 2nd order 100 % staror protection in generator protection uses 3rd order overexcitation uses 5th order thanks

The current in the secondary side of a CT (Current Transformer) is induced by the current flowing in the primary circuit. If the current continues to flow in the primary circuit and the CT is left "Open Circuit" then dangerous voltages can build up and cause damage to equipment when reconnected or personal injury by electric shock.

Therefore, shorting the secondary terminals of the CT allows current to circulate taking flux with, thus reducing the building up of flux; the higher the flux the higher the emf (voltage) induced; E = Blv.