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Electrical Engineering
Electrical engineering is a field of engineering that deals with the study and application of electricity, electronics and electromagnetism.
23,056 Questions
How bright is 3000 kelvin in watts?
It is very hot. The answer is 29726.85 C (approx.). The Kelvin scale starts at absolute zero and is used in scientific laboratories. Celsius is for general use and set 0 and 100 as melting and boiling point of water respectively. To convert from K to C, subtract 273.15 from K.
What type of oil is use in transformer?
That depends on the unit. Normally mineral oil, sometimes silicone or wecosol, sometimes askarel.
Can 3 phase power and single phase be ran in the same conduit?
Yes they can. There are regulations that cover most jurisdictions regarding how different cables can be contained. It is important that you are knowledgeable about your local requirements before starting the work.
What is the relationship between resistance and temperature?
• ntc 'negative temperature coefficient': its resistance decreases as the temperature increases
• ptc 'positive temperature coefficient': its resistance increases as the temperature increases
IEEE stands for Institute of Electrical and Electronics Engineers. It is an organization made up of engineers, scientists and students who develop standards for the computer and electronics industry.
What is a conductor and what is the use of it?
The root word comes from the Latin, and means 'to lead'. The 'duct' part is the 'lead' part, and we meet it in conducive, conduct, duct, ductile, and so on.
Conductors are used to transfer energy or a material from one place to another. We have conductors for heat, sound, vibration, electricity, and so on.
A word with the opposite meaning is 'insulator'.
as frequency is reduced current gets increased winding gets heated.current goes up.voltage gets dropped.power also gets dropped.
Why you should not drink water after electric shock?
No reason that I know of - assuming you are no longer being shocked.
It could depend on the severity of the shock though. With high voltage electrocution comes burns, and often the burns are internal. If the voltage passed through your gastrointestinal system, adding anything to it, even something as innocuous as water can cause greater issues.
Why rated current should flow in the secondary for short circuit test in transformer?
Open Circuit test is done to find out core losses of the transformers.which include Eddy Current Losses and Hysteresis Losses only, if during open circuit test secondary will have some load then I2R losses due to load current in secondary as well primary will be included in test results which is not desired while performing Open circuit test.
Does increasing the voltage across a resistor increase the electric current through the resistor?
Resistance is not affected by either voltage or current. It is determined only by the cross-sectional area, length, and resistivity of the material. As resistivity is affected by temperature, resistance is indirectly affected by temperature.
In the so-called 'Ohm's Law' equation, resistance is a constant. So, if you increase voltage, the resistance remains constant, and the current would increase in proportional to the voltage.
Why are electrical devices rated with both a voltage and a current?
The short answer is you need power. And power is the product of voltage and current: P = V*I. As either V or I approaches zero, P approaches zero. So, you need voltage and current flow to generate the power needed to operate an electrical circuit.
Yes, that's because the voltage output of an alternator is restricted by the number of windings that can be slotted into its armature, restricting its output voltage to just 25-30 kV, which is far too low for transmission purposes.
How are the safety devices in an electrical circuit connected?
Heaters,Electric blankets,clothes dryers,stove ,oven,cook top,
Hot water cylinders,Plugs,Multi-boxes,Lighting,Cords and leads,small-appliances,Current flow 5amps in a 120v circuit . what would the resistance be?
The current flowing through a circuit is equal to voltage divided by resistance:
I = U / R, and therefore R = U / I.
With your given data, R will be 24 Ohms.
It is helpful to remember following figure:
U
I R
If you ever want to calculate one of those values, cover it with your finger, and the rest will look like an equation. For example, when looking for I, cover I and the rest of figure gives you U over R.
What are two uses of capacitors in an ac circuit?
power factor correction, and sometimes it is necessary to place capacitors in series with a line to counteract the natural inductance of the line - this allows more power to be transferred through that line.
Motor will rotate at very high speed leading to destruction
Answer from Kinindia.com
What are the factors causing a permanent magnet generator not to generate emf?
A magnetic field will not generate an EMF if there is no motion, so the primary factor causing a permanent magnet generator to not generate EMF is if it is not turning.
What is difference between an AC and DC flux?
As happens with voltage and current, flux is steady for dc but keeps altering for ac.
A transformer works through the ac flux in the magnetic core.
What is principle of Current transformer?
why does have to short-circuit secondary wire of current transformer ?
If 10 coulombs of charge passes a specified point in 2 seconds how much current is flowing?
10/2 = 5 coulombs per second = 5 amperes.
It is an electric generator driven by a rotating shaft that generated electric power in three-phase form. The other name for one of these is an alternator.
Alternators are used almost exclusively to generate electric power in power plants across the world. The power is then transformed to appropriate voltage levels on its way to the consumers.
An alternator has a set of three pairs of fixed coils on the stator, and a single coil fed with direct current through slip rings on the rotor.
Alternators are also used to generate electric power in cars. In this case the power is fed through a full-wave rectifier using six diodes to connect the power directly to the car battery. The voltage is controlled by an integral device attached to the alternator that controls the current fed to the rotor. Current for this is taken from a half-wave rectifier using another three diodes, and it is passed through the ignition switch.
Which type of oil should be used in transformer?
Environmental safety in case of spillage.
- There has to be a dyke wall for oil containment in case of spillage so that the oil does not get into ground / land.
- Oil level must be maintained at required level with a suitable breather and Silica gel arrangement
- BDV of the Oil must be regularly tested and minimum value must be maintained.
- Oil Cooling arrangement must be maintained.
- No leakage in radiators.
What is circuit that is complete and unbroken with flowing electric current?
Yes, as long as the unbroken path is a good conductor of electricity.
