0
Electrical Engineering
Electrical engineering is a field of engineering that deals with the study and application of electricity, electronics and electromagnetism.
23,056 Questions
answer by engr ZOHAIB MUSHTAQ WHEN EMF APPLY AT TWO DIFFERENT ENDS OF METALLIC PLATE HAVING COMBINE JUNCTION HERE ONE END IS HOT AND OTHER END IS COLD THIS EFFECT IS PELTIER EFFECT
What produces more light series or parallel circuits?
A series circuit will produce more voltage. For example, two 12 volt automotive batteries both have a 600 amp capacity.
Connect the 2 batteries in series and you will have 24 volts with 600 amp capacity.
Connect the 2 batteries in parallel and you will have 12 volts with 1200 amp capacity.
What property of a wire increases when it is made thinner?
It's resistance to electric current increases.
Do additional resistors affect power?
Of course. Additional resistors change total resistance, which changes current, which affects power.
Nowadays power cuts are happening in the peak usage timing such as from 6:00 PM to 10:00 PM. This is happening because the power requirement in these times is very high as compare to other off-peak timings. Unnecessary usage must be avoided to eliminate this problem. In many countries electricity providers are implemented TOD based energy meter to reduce the usage of electricity by increasing rates in Peak hours and reducing rates is Off-peak hours. Time of Day metering (TOD), also known as Time of Usage (TOU) or Seasonal Time of Day (SToD), metering involves dividing the day, month and year into tariff slots and with higher rates at peak load periods and low tariff rates at off-peak load periods. While this can be used to automatically control usage on the part of the customer (resulting in automatic load control), it is often simply the customers responsibility to control his own usage, or pay accordingly (voluntary load control). This also allows the utilities to plan their transmission infrastructure appropriately.
How many output amps is a 75 KVA generator?
It depends upon the Generator system voltage. For 3 Phase, 600 Volt system, it will be 73 Amps For 3 Phase, 480 Volt system, it will be 90 Amps For 3 Phase, 208 Volt system, it will be 208 Amps
What is the difference between watt and KVA?
VA or volt-amps is also volts times amps, the concept however has been extended to AC power. For DC current:
VA = Watts (DC current). In AC if the volts and amps are in phase (for example at a resistive load) then the equation is also:
VA=Watts (resistive load)
where V is the RMS voltage and A is the RMS amperage.
Why didn't they complete a maglev train in the UScities?
It's all to do with magnetic repulsion - when the train is moving, the two magnets have the same pole, and so repel each other, creating a "cushion". It's a bit like the principle of two bar magnets in school, matching north pole to north pole.
What are the different electrical symbols?
In electrical engineering there are many types of symbols used to notate devices. These include symbols for polarity, switches, diodes, and batteries.
How do you measure RPM of a motor?
The speedometer and speedometer cable tells the driver how fast the vehicle is going. What's called a Hall-Effect sensor is used. It uses the principle of magnetic inductance. When a magnetic flux passes through coils of wire, voltage is generated. To use this effect, a magnet is placed in the cars differential. The sensor then can tell when the magnet comes around by a spike in voltage. Since there is a constant amount the car moves with each differential rotation, and with the time between voltage spikes, you can easily divide to get the speed. This is why changing your cars tires will affect your speedometer. Your car assumes that car moves a certain amount with each differential rotation. If you have larger tires on, then each differential rotation (and axle rotation) your car moves further, and you'll move faster than indicated.
speedometer
speedometer.
A speedometer or Machmeter.
The instrument that is used to measure speed is called a Speedometer. This may sound obvious, but it is the correct name for the instrument. All motor vehicles by law will have this.
The device used to measure the speed of the car is known as speedometer.
Transmission output sensor is usually used as the input sensor for the speedometer, also the braking system uses the wheel speed sensor to determine if a wheel is slowing faster(locking up).
When you plug in more appliances in your home why does the current increase?
That happens when the appliance supplied by the outlet is switched off.
What is the difference between electrical choke electronic ballast choke?
Ballast is purely a coil simply inductor that controls the current supplied to the tube. Of which there will be some loss and drop in power factor. Yet it is a good system which can handle the voltage fluctuations in the input. An electronic choke has 2 diode bridges and 2 major capacitors, by which the voltage and current supplied are controlled. The circuit operates in three stages. Voltage boosting is good and immediate, also eliminates starter. But this creates harmonics in the system which may disturb other systems if produced in large and it also cant handle the fluctuations.
What is the working principle of fan regulator?
n electrical regulator by using resistance the output voltage is varied simultaneously the speed is varied... But to reduce the the energy loses in the resistor, electronic regulator is introduced,which uses triac to vary the output voltage by varying the firing angle.Which avoids lose of energy in resistor...
In motor winding what is the difference between a lap winding and a wave winding?
When electricians and electrical engineers/repairmen are called upon to assess troubles in generators and motors, they often rewind different types of these machines. There are two families of armature (closed-circuit) windings: lap winding and wave winding, described by the commutator pitch used for winding. In mechanical terms, armature windings consist of coils connected to a commutator in Read more....direct-current machines; or coils are connected together in alternating-current machines to form groups or series.Lap winding, also called parallel or multiple winding, is the process of winding elements or coils lapping back when wound on armature cores. Lap circuits are connected in parallel between brushes. The front and back pitches are odd with opposite signs. Winding pitch equals the algebraic sum of the front and back pitches. The end of a coil is connected to the commutator and the start of the next coil under the same two poles. Single-lap windings always have the same number of current paths as field poles while double-lap windings have twice as many current paths as field poles. Triple-lap windings have three times the number of current paths as field poles.The zig-zag or wavy path of winding through slots of armatures defines single (two-circuit) wave windings and multiplex (series-parallel) windings. Half of the armature coils is connected in series and the other half is connected in parallel between brushes, no matter the number of poles. Winding pitch is equal to the sum of the front and back pitches, which both must be odd with the same sign. The end of a coil is joined to the armature and the beginning of another under the next two poles. A single-wave winding has two current paths between brush sets. The double-wave winding has four current paths between brush sets; and the triple-wave winding has six current paths.Wave winding is used mostly in small and medium sized machines (500-600 volts) for keeping the number of coils as small as possible. Applications requiring high voltages at low currents use wave windings while lap windings are used for lower voltage, higher current applications. Wave windings, for a given number of poles and armature conductors, give more emf (electric and magnetic fields) than lap windings.Examples of suitable symmetrical armature windings for DC-machines with different poles are: for two-pole machines, two-circuit lap winding is preferred over wave winding; for four-pole machines, two-circuit wave winding or four-circuit lap winding is suggested. Six-pole machines should use two-circuit wave or six-circuit lap winding since four-circuit wave winding is asymmetrical.
How do you increase the frequency of Alternating Current?
There are two ways. If you want to increase the frequency by a huge amount and you want to do it on a permanent basis, install more magnets. An alternator that has one pair of field magnets and that turns at 3600rpm will generate 60-hertz electricity. If you put two pair of field magnets in it and turn it 3600rpm, it will generate 120-hertz electricity, and so on and so forth. (The other side of that is, if you want a certain frequency of electricity, the more pairs of magnets you install the slower the alternator has to turn. Install four pair of magnets in the generator, and you only need to run the engine at 900rpm--which makes it much quieter, a big advantage if the generator belongs to the army.) If you just need to adjust it a little, simply rev up the engine. If you have a generator that makes 60hz power at 3600rpm, accelerating the generator to 3660rpm will cause it to make 61hz electricity.
What do you think would happen to the winding if the current were sustained for a few minutes?
Will damage
How do you you get a voltage mythie in jumpstart?
First you must become a member.
After this goto the Mythie Sanctuary & collect 15 hearts. Once this task has been completed you are given a egg which you can decorate & name. In a couple days the egg will hatch & you'll have a Mythie in need of training.
If you can get to the Mythie Sanctuary then the Jumpstart characters will walk you through the process.
How do you connect a single phase capacitor start induction motor forward?
This is for a single voltage motor. If you consider the forward rotation as counter clockwise (CCW) when looking at the motor from the end opposite the drive end, then the connections will be, L1 - terminals 1 and 8, L2 - terminals 4 and 5.
To reverse the rotation (CW), then the connections will be, L1 - terminals 1 and 5, L2 - 4 and 8.
Diff between electrical and electronics?
Where as "Electronics" relates more to the complex functions performed within a given device, more often now days by circuits comprised of many micro electronic sub components that make up the structure of a single micro electronic component. Example: a typical CPU chip would / could contain thousands of individual transistor circuits within a device no bigger that the size of your small finger nail with room to spare.
In short: electrical circuits handle transfer of energy - electronic circuits handle transfer of information
what is the main difference between electrical and electronics ?
In short: electrical circuits handle transfer of energy - electronic circuits handle transfer of information
HOW TO CALCULATE THE IMPEDANCE FOR THE TRANSFORMER?
The term, 'percentage impedance', is a little misleading, as it is defined as 'the value of primary voltage that will cause rated current to flow in the secondary winding, expressed as a percentage of the rated primary voltage'.
So, the test is carried out as follows: the secondary winding is short-circuited through an ammeter capable of reading the rated secondary current. A variable voltage is applied to the primary winding. The primary voltage is gradually increased until the ammeter indicates rated secondary current. That primary voltage is then expressed as a percentage of the rated primary voltage -and that value is the transformer's 'percentage impedance'.
What is power factor of an R-L series circuit?
Power factor is real power divided by total power. Power factor can be written as:
pf = R / sqrt(R^2 + X^2),
where X is the reactive resistance of the active elements (in this case, L):
pf = R / sqrt (R^2 + (wL)^2)
w = frequency in radians of the AC frequency for which the power factor is to be calculated.
It glows because the filament wire is exposed in a vacuum and electrically, the light is a high resistance load. You know the sparks you get when you rub two exposed hot electrical wires together? That's a dead short. Now, put that short in a vacuum where the wire can't oxidize, and presto! Incandescent light. The filament is made of tungsten, and tungsten has a very, very, very high melting point. It took Thomas Edison a long time to find it, but find it he did.
