Electrical Engineering

For comparing cost copper requirement is necessary

copper in 3 phase = .75(copper in single phase)

i.e. less cost in 3 phase when

1. line voltage is same

2. equal power input

3 same power loss

When the phase voltage is same & 2,3 conditions met then equal cost.

1st writer: You have Ohms law written wrong, here is an easy formula to use to get the right answer: V/IxR but the answer is .2 Amps (note the right answer)

2nd writer: You both have it written wrong. Ohm's Law is V=IxR. This can be used to solve Voltage, Current and Resistance with two givens. Then, when Power is presented through Watt's Law (P=IxV), you are able to solve for any of the four also with two givens. http://www.aob.com.au/resources.html Here's OUR set-up: I=V/R

This is the substitution: I=12V/60Ω Answer=0.2A OR 200mA

At the typical U.S. home, the voltage at the wall outlet is somewhere between 110 and 120 Volts AC. Most U.S. homes also have 220 Volts (which is actually somewhere between 220 and 240 VAC) available, but not wired to most rooms.

voltage over resistance/impredance.

V

/

I * R

V= Voltage

I= Current

R= Resistance or Impedance

Cover what you want to know and the way the other two are laid out gives you your equation.

Your question is wrong. Kwh is a unit of energy, mw is a unit of power .

1kw=1000000milli watt(mw)

1kwh=1000000mwh

A capacitor consists of two plates separated from one another by an insulator. These plates are normally thin foil and can be sandwiched around a very thin insulator and wrapped into a small package. Since there is an insulator between the plates, DC connected to the two plates cannot flow as long as you do not exceed the breakdown voltage of the insulator. AC current is a different story. Because the insulator is very thin and the effective plate area is relatively large, a negative charge building up on one plate causes electrons to be repelled from the opposite plate, and as the charge on the first plate reverses and becomes positive, the electrons in the opposite plate are attracted back again. This results in a matching alternating current flow on the opposite side of the capacitor.

If you are referring to the voltage at your residence, then voltage variation is caused by the changes to the load on your supply network. The network load varies throughout the day, being busiest, for example, around lunchtime and around dinnertime. The resulting load current variation causes the supply voltage to vary (it drops when the load current increases) but, by law, your supplier is obliged to maintain any voltage variation within limits -in the UK, for example, these limits are between +10% and -6% of the nominal 230 V.

The rotor is made up of laminated steel discs that are pressed on to a common shaft. This shaft has bearings mounted on either end which allows the rotor to spin within the frame of the motor. The shorting bars on the rotor are usually made of aluminium.

Energy changes from ball to ball down the accelerator just as it does in Newton's cradle. It functions on the transfer of momentum.

Stator is part of rotating mechanical device thats sorrounds the rotor to rotate it through the induced magnetic field while the Rotor, is the one who is rotated by produced magnetic field in the stator,.

The resistance of a simple conductor normally rises as its temperature rises.

Armored electrical cable contains insulated electrical service wires protected by a flexible steel covering. Unarmored electrical cable has no protective flexible steel covering, its covering is made of plastic.

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Armored cable (BX) is the older version of Metal Clad cable (MC). It was flexible steel covered wire that used the steel as it's Ground. BX was a poor grounding system so it was replaced with MC which looks similar but has a separate Grounding conductor. MC is most often made with aluminum as its cover.

Armored cable if used today will refer to MC type wiring.

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Some kinds of armored cable are in fact made to a tougher standard than the ordinary soft wire strand types of shielded cable that are used for hooking-up antennas. The 'armor' is actually a thin flexible metal film that better protects the wire or wires inside from damage in high use or high traffic areas. Such kinds of armored cable are also used in radio frequency assemblies in electronic equipment.

universal motor r mostly used for domestic purpose applicatios like the vaccum cleaner,foodprocessors and mixeshair driers,coffee grinders,electric shavers etc....another applications for blowers.

Fusing currents is combining two or more wires together to join the currents. A critical factor is the temperature of the wire.

To stop a three-phase motor dead ('plugging'), rather than allowing it to slow to a stop, the motor controller interchanges two of the three lines -which applies a reverse torque to the machine. But before the motor then gets a chance to reverse direction, the centrifugal switch trips the starter and removes the supply.

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The centrifugal switch that you refer to and can see in an open frame motor, is used to open the start winding of small HP single phase motors. Once the motor gets up to a certain RPM, the switch opens and the motor continues to operate on its run winding. When the motor stops, the switch goes back to its normally closed position in the start winding and awaits the next start operation.

A differential in an automobile is used to transfer the power to rear drive axles from the transmission in rear wheel drive vehicles. In 4-wheel drive, the two differentials transfer power from the transfer case to the wheels. Most front wheel drive vehicles use a transaxle which combines a transmission and differential in the same case. Again, one of the roles is to transfer power to the wheels.

However, it does more than that. It allows one wheel in the set to turn faster than the other. That is so the vehicle can negotiate curves without skidding.

#1). Thinner wire.
Either replace a wire with one composed of thinner material, or
stretch the existing wire slightly so that it becomes thinner.

#2). Longer wire of the same thickness.

By using a simple formulae: f=np/60 where f= frequency, n is the number of pair of poles and 60 is in seconds that motor is turning. So a 4 pole motor with a frequency of 50 hertz will run at 1500 rpm.

By manupilating the formulae:

n= 50 multiplied by 60 devided by 2

therefore n= 1500rpm.

The formula 120xFrequency/poles gives synchronous speed not actual shaft RPM. Induction motors must run at a certain % slip to obtain torque, so a 4 pole motor running at 50hz would be 120x50/4 = 1500 rpm, at 4% slip (operating speed) actual shaft RPM or rated speed would be 1440 RPM.

Voltage series feedback amplifiers can suffer from reduced input impedance, which may affect signal source loading. They can also introduce phase shifts that may lead to stability issues. Conversely, voltage shunt feedback amplifiers can lead to increased output impedance, which may limit their effectiveness in driving loads. Additionally, both configurations can experience bandwidth limitations due to feedback network design.

If you connect 50 Hz current , it may signal to 60 Hz sub-woofer than nothing will happen your sound system will play simply. but mind the amplitude or voltage of applied signal. if you increase voltage which is far then the range than your system may damage.

A; By using a voltmeter across a small shunt resistor

two wires carrying currents in opposite direction repel each other because the magnetic field between the wires is strong than on the sides of the wires.wires will move towards the weaker magnetic field from stronger field