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Electrical Wiring
Ask questions here about proper wiring and electrical installation here.
4,935 Questions
How does current flow in a conductor?
Current flows in a conductor when there is a potential difference applied across it, creating an electric field that causes the movement of free electrons in the conductor. The electrons flow from the negative terminal to the positive terminal of the voltage source.
How much electricity does a electric horse fencer use in one day?
This question cannot be answered correctly without a little more information. How big is the fencer? How many joules/amperes/watts/volts... And how much fence are you wanting it to electrify? 200 feet or 5 miles? Unless you are running a high-powered fence in heavy grass over a long distance, most fencers generally use less wattage daily than a incandescent light bulb. You asked a vague question and got a vague answer. Hope that's what you wanted!
How do you shock someone with static electricity?
To shock someone with static electricity, build up as much charge as possible by shuffling your feet on a carpet or rubbing a balloon on your hair. Then, touch the person with your charged body to transfer the electric shock.
Where is nuclear energy stored?
Most of the energy in a nuclear power plant is due to the neutrons. The half-life of a free neutron (a neutron no longer bound to an atom) is about 15 minutes, before it breaks down by radioactive decay.
When emitted from an atom in a radioactive decay, it is traveling very fast. It may be slowed down by using a moderator - a material in which it has a high likelyhood of a collision. Since it spends longer in the moderator, there is a greater probability of the energy of the breakup being contained within the moderator.
In its decay, it emits energy, and this is perceived as heat, and may then be used to drive a steam generator to make power.
So the energy is stored as the element of structure of the neutron, and when that structure breaks down, the energy is emitted. (or at least that part that was binding energy in the neutron).
What you are asking is kinda like asking how many oranges in an apple
Voltage is the measure of electrical potential
Amps is the measure of electrical quantity
a good illustration is a water pipe, you can have high pressure (volts) but unless the water is allowed to flow the quantity of water is zero. (amps)
The dielectric strength refers to the maximum working voltage that a material can withstand without breaking down. At breakdown the electric field frees bound electrons turning the material into a conductor.
How does a solar panel absorb energy from the sun?
There are two types of solar panel, the solar thermal collector, and the photovoltaic cell. The first simply collects thermal energy from the sun and transfers it to a fluid, usually water. this is quite useful for domestic hot water, warming swimming pools, and can be used industrially to prewarm feedwater. The photovoltaic cell responds to visible sunlight and produces a small dc current from semiconductor material such as silicon, doped with impurities. The theory says that photons of light energy cause electrons to be displaced resulting in a current flow. In bright sunlight it takes 1 square meter of cells to produce 120 watts of power, but this is only available at peak sun intensity during a 24 hr cycle. These figures are for the first generation of cells, much work is ongoing to improve efficiency and make production cheaper.
Single-phase voltage and frequency
Countries in Europe and in many other areas of the world use a standard mains supply voltage for households and businesses of between 220 and 240 volts for lighting as well as for high-powered appliances. This is twice that of the voltage used for ordinary lighting and low-power appliances in US, Canada and most of the Americas, and also Japan. In those countries, and others using the same power distribution system, the standard mains supply voltage for low-power appliances is between 115 and 127 volts.
Note that currently all new American buildings in fact get 240 volts split into two 120 volts "hot" wires (often called "legs") with a common neutral wire. Major appliances, such as virtually all drying machines and ovens, are now connected to 240 volts.
The mains frequency in Europe and other 230 Volt areas is 50 Hz (Cycles per second) compared to 60 Hz in US, Canada and other 120/240 Volt areas. Some 60 Hz appliances will work fine but others with simple motors will run too slow on the lower frequency of 50 Hz. Similarly, some 50 Hz appliances will work fine but others with simple motors will run too fast on the higher frequency of 60 Hz.
However the most important difference is how the Neutral wire is connected:
240 volt 50 Hz service
A 240 volt 50 Hz appliance can have up to 3 wires altogether:
- one single 240 volt "live" or "hot" wire;
- a neutral wire;
- a safety "earth" or "ground" wire but this is not required if the appliance is of the type known as "double insulated".
The hot wire feeds alternating voltage from the power station to the load and, because the voltage is alternating, the load draws an alternating current. Then the neutral wire returns the current to the power station to complete the circuit.
240 volts 60 Hz service
An appliance that is designed to be connected to strictly 240 volts 60 Hz is connected with only a two wire cable plus a safety ground wire. (For example 240 volt 60 Hz base board heaters use that.)
The only time a cable with three wires plus safety ground is used is if 120/240 volts is needed in the equipment. (For example kitchen ranges or washing machines which have time clocks or programmers that require only a 120 volt feed.)
Thus an appliance designed to run on a 240/120 volt 60 Hz supply can have up to 4 wires altogether:
- two 120 volt 60 Hz live "hot legs" which run in opposing phase to one another: when one hot leg goes "+" (120 volts positive) the other leg goes "-" (120 volts negative);
- a neutral wired as a "central" common current return conductor:
- a safety "ground" wire but this is not required if the appliance is of the type known as "double insulated".
One of the two hot wires feeds a 120 volt alternating voltage from the power station to the 120 volt load - the clock or programmer - and, because the voltage is alternating, that load draws an alternating current. Then the neutral wire returns the current to the power station to complete the circuit.
Important conclusion
There is a 240 volt voltage difference between the neutral and the hot conductor in the 50 Hz system and only a 120 volt voltage difference between the neutral and each of the hot conductors in the 60 Hz system.
That is why an appliance designed to be connected onto the 50 Hz system cannot be used safely on the 60 Hz system without first having a proper technical inspection done, followed by any necessary modification work done to ensure that the appliance can be operated safely because, in the main breaker box, at the point where the 60 Hz "neutral" gets connected to the ground, this difference will cause serious problems!
A licensed electrician or electrical engineer would be able to consider whether or not a particular large appliance, that was manufactured to work on 50 Hz-only, could be modified to run safely at the higher 60 Hz frequency. However it won't usually be worth the expense of doing the work because it would be more cost-effective to buy (new or secondhand) an equivalent large appliance designed to work on 60 Hz.
The system of three-phase alternating current electrical generation and distribution was invented by a nineteenth century creative genius named Nicola Tesla. He made many careful calculations and measurements and found out that 60 Hz (Hertz, cycles per second) was the best frequency for alternating current (AC) power generating. He preferred 240 volts, which put him at odds with Thomas Edison, whose direct current (DC) systems were 110 volts. Perhaps Edison had a useful point in the safety factor of the lower voltage, but DC couldn't provide the power to a distance that AC could.
When the German company AEG built the first European generating facility, its engineers decided to fix the frequency at 50 Hz, because the number 60 didn't fit the metric standard unit sequence (1,2,5). At that time, AEG had a virtual monopoly and their standard spread to the rest of the continent. In Britain, differing frequencies proliferated, and only after World War II was the 50-cycle standard established.
However that might have been a mistake! Not only is 50 Hz 20% less effective in generation, it is 10 - 15% less efficient in transmission and requires up to 30% larger windings and magnetic core materials in transformer construction. Electric motors are much less efficient at the lower frequency, and must also be made more robust to handle the electrical losses and the extra heat generated. Today, only a handful of countries (Antigua, Guyana, Peru, the Philippines, South Korea and the Leeward Islands) follow Tesla's advice and use the 60 Hz frequency together with a voltage of 220 - 240 V.
Originally Europe was 120 V too, just like Japan and the US today. It has been deemed necessary to increase voltage to get more power with less losses and voltage drop from the same copper wire diameter. At the time the US also wanted to change but because of the cost involved to replace all electric appliances, they decided not to. At the time (1950s-1960s) the average US household already had a fridge, a washing-machine, etc., but not in Europe.
The end result is that now it may seem, to some people, that the US has not evolved from the 1950s and 1960s, and still copes with problems as light bulbs that burn out rather quickly when they are close to the transformer (too high a voltage), or just the other way round: not enough voltage at the end of the line. (115 to 127 volt spread!).
For more information see the answers to the Related Questions shown below.
If you are interested to know what what the different standard mains voltages and frequencies are around the world - and what the various plugs look like - the Related Link shown below has all the details.
Why is a good conductor of electricity also a good conductor of heat?
We know that a conductor allows electricity to move through it. Conductors have a source called mobile electrons that go side to side inside the conductor itself when an external source connects to it their source goes through the conductor allowing electricity to flow.
The gaseous cycle refers to the movement of gases such as oxygen, carbon dioxide, and nitrogen through different parts of the Earth's ecosystem. These gases are constantly being exchanged between the atmosphere, organisms, soil, and bodies of water through processes like photosynthesis, respiration, and decomposition. The gaseous cycle is essential for maintaining the balance of gases in the atmosphere and supporting life on Earth.
When the conversion of a system, process, etc. Is completed in phases rather than a complete transformation at one time.
What makes a light bulb glow when a lamp is turned on?
In an incandescent light bulb a small coil of thin tungsten metal - which is not such a good conductor of electricity as copper - resists the flow of current so much that it heats up. The thickness of the tungsten is carefully designed so that it gets hot enough to give out visible light but does not get so hot that it melts and breaks.
Another answer
Inside the bulb is a wire that goes to a piece of coiled tungsten (a heavy metallic element). This causes maximum resistance to the electricity flowing through the wire. The resistance causes the tungsten to heat up to 4,500 degrees F, so much that we see the glow as light. The glass bulb surrounding it contains an inert gas, protecting the filament from oxygen which would cause it to burn out immediately and also prevents contact with the white hot metal.
For more information please click on the Related Questions shown below.
Whats 2 examples of chemical energy?
(more than two) Chemical Energy Examples: Digestive process, batterys, photosynthesis, burning gasoline, burning wood, using TNT, fire works, putting salt on a slug, alchohol, fermintation, rusting. (all of those answers where aproved by my physical science teacher)
Who invented the light bulb filament?
Thomas Edison is credited with inventing the first practical incandescent light bulb filament in 1879. He used a carbonized bamboo filament that gave the bulb a longer-lasting and brighter light compared to previous designs.
What frequency of a wave in the air can be heard as an audible sound by the human ear?
For the human ear, sound is audible in the range of 20 Hz (Hertz) to 20000 Hz. Sounds below 20 Hz are "infrasonic" and have too low a frequency to be heard; sounds above 20000 Hz are "ultrasonic" and are too high a frequency to be heard.
What is the scientific definition for intensity?
Intensity is proportional to the square of the amplitude of vibration in case of mechanical wave such as sound waves
But in case of light which is electromagnetic in nature, the intensity is the number of photons crossing unit area in one second
What is an example of an electrical insulator?
Better to say that they resist the flow of charge - rather than 'don't let electricity flow through them'.
How do you convert single phase supply to three phase for running a 3-phase motor?
Any business, such as a factory, or any home needing a 3-phase supply for some equipment would usually get that supply by having it installed by their local electric power utility company.
For a very small 3-phase motor, solid state power inverter units are available nowadays which can be powered from household 1-phase supply.
If you want to know how to convert a 1-phase to a 3-phase supply for high power applications it can be done using a motor/alternator set or a solid state inverter unit but to use these safely requires specialized equipment and electrical engineering knowledge. The full answer is too complicated to explain here.
Depending on the amount of money you want to spend to make this happen there is a device on the market called a VFD ( Variable Frequency Drive). On the three phase input terminals you apply your single phase voltage. On the output terminals you connect your three phase motor. When run in this configuration there is an internal switch that has to be changed to let the VFD know that it should be looking for only two lines on the input to be hot. Other wise the VFD thinks that there is a line loss on the three phase input terminals and the unit will not start.
Before you do any work yourself,
on electrical circuits, equipment or appliances,
always use a test meter to ensure the circuit is, in fact, de-energized
IF YOU ARE NOT REALLY SURE YOU CAN DO THIS JOB
SAFELY AND COMPETENTLY
REFER THIS WORK TO QUALIFIED PROFESSIONALS.
What is a electric shock and what happens?
An electric shock is a sudden flow of electric current through the body. It can cause a range of symptoms depending on the severity, including pain, burns, muscle contractions, and even stoppage of the heart in severe cases. It is important to seek medical attention immediately if someone has experienced an electric shock.
If you are in doubt as to whether or not electricity jumps, take a look at how a spark plug works in a car. Electricity can jump and the distance depends on the voltage. The higher the voltage, the further it jumps. You don't have to touch something electrical to get a shock, you just need to be in close proximity to it.
This is why in the UK many bathrooms and toilets have a pull cord instead of a light switch, simply because it is not a good idea to touch a switch with wet hands, due to the fact that electricity can jump and water is an excellent conductor.
The mains voltage in the UK is 230V (enough to kill you instantly). Shaver sockets in bathrooms in the UK pump out 110V (still enough to kill, but not likely). The risk of shock still remains the same and so that is why the voltage is lowered.
A typical household in the UK will receive a 230V supply at 100amps. (Please note it is the current (amps) that kills and not the voltage. A spark from a static electric shock can reach 1,000V). The current coming into the house is usually split in the following way: 30A to the immersion heater, 30A to the electric cooker and the remaining 40A gets used for lighting and power sockets (outlets).
If you are still uncertain about electricity jumping, in the UK, construction sites are only allowed to use 110V on site to minimise electric shock. If you are a miner and end up going a long way down underneath the earth, you will find that the electric supply will carry only 50V. Believe it or not a shock of 50V underground can still kill instantly because you are heavily earthed simply because of all the earth around you. Think what 230V would do underground!
On a final note, don't let anyone tell you electricity cannot jump. Surprisingly my boss said that and how wrong he was!
How do humans use solar Energy?
Humans use solar energy to charge batteries to heat homes, pools, and even to create electricity. Solar energy is also used to charge electronic appliances, grow algae for feeding fish, and heat entire buildings.
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True, but you've missed something rather closer to home. We as living organisms need the Sun's light and heat directly for our physiology, and indirectly from needing to eat - our food plants and animals similarly need solar radiation to exist and thrive!
Here are some possible answers: a) If you hold a compass close to a wire you may see the needle move. How much it moves depends on the strength of the current flowing in the wire. If the needle doesn't move then there may be three explanations: 1) No direct current was flowing in the wire OR 2) a direct current was flowing but it was too weak to make the compass needle move OR 3) there might have been a current but it was an alternating current changing so fast that the needle did not seem to move.
b) If the bulb in an electric circuit was lit but then blows, it may mean one of two things 1) the current was switched off so the bulb went out OR 2) the bulb just died, in which case any current that was flowing in the bulb's circuit would stop. c) when the plug of an iron is placed into a socket, if it warms up then a current must be flowing from the socket to the iron. But before the iron was plugged-in, no current was flowing. Now you work out which of those answers to this question is the right one!
No, nonmetals are typically not magnetic because they do not have unpaired electrons in their outer shells, which are necessary for exhibiting magnetic properties. Materials must have unpaired electrons to create a magnetic field.
Metals conduct electricity due to the presence of free-moving electrons in their atomic structure. When a voltage is applied, these electrons can move through the metal, creating an electric current. This high mobility of electrons in metals is what allows them to be good conductors of electricity.
Carbon, in it's graphite form, is a semiconductor. But not in it's diamond form. Materials such as metals, conduct electricity do so because when their atoms are arranged together in a solid, they have loosely bound electrons which can easily move through the material if an electric potential is applied to it. For instance, in a copper lattice, there is about one free electron available per atom of copper for conduction, which makes it a very good conductor of electricity. But, carbon holds on more tightly to its electrons so they are not as free to move from place to place as in the case of copper or other metals. It is one of a number of elements known as semiconductors. Its neighbor, one row down on the periodic table, is silicon, which is used for most commercial microchips produced today. In a semiconductor, electrons can't just flow through the material. They have to move from atom to atom in "jumps", according to the laws of quantum mechanics. When they jump, they leave a positively charged "hole", which can be later filled by another electron jumping in to take the first electron's place. Under the influence of an electric potential, one sees a slow movement of negatively charged electrons in one direction and positively charged "holes" in the other direction.
