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by Ron Kurtus

A total of 724 comments and questions have been sent in. They are listed according to date.

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List of next 10 letters




Electricity Resources Converting AC electric motors Ethiopia
Electricity Understanding an AC generator UK
AC Transformers Changing AC to DC electricity India
AC World Voltages Can I use 60Hz radio with 50Hz? USA
Electrical Charges When atoms lose electrons. USA
AC Transformers How are transformers used to distribute electricity? USA
Electricity Basics How can electrons move in a vacuum? India
AC World Voltages Air conditioner not running well with Guam electricity Guam
Electricity Basics Will DC current readily flow through a conductive gas? USA
AC Why does AC change direction twice per period? Cambodia

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First 10 letters

Converting AC electric motors

Topic: Electricity Resources


August 1, 2013

I am railway civil engineering student in Addis Ababa University of Ethiopia. My question is related with AC motors. What is the reason, why AC motors are not converting electrical power supplied from AC sources to AC?

Adnew - Ethiopia



A synchronous AC motor will only run smoothly at the frequency of the sine wave. Another type of AC motor is an inductor motor. But that has a number of problems.

In some cases AC is converted to DC to power the motor.

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Understanding an AC generator

Topic: Electricity


May 27, 2013

Hi my name is James and I am currently training to become an electrician in the Uk, a lot of my work involves a good understanding of the fundamentals of electricity so this is where I concentrate most of my efforts, I have found myself stuck trying to understand parts of AC generation so I am writing to you to ask if you could possible answer my question.

My question regards a.c generators and how is a potential difference really established?

My guess is that potential difference (voltage) in a generator is between the two sides of the coil, but how is this established? my understanding of potential difference tells me that for there to be a difference in potential there has to be un-even amounts of electrons between two points, where one point posseses to many and the other possesing to little thus there is a potential difference betweeen the two in which the electrons will desire to travel from the higher potential to the lower potential point.
So as a guess I would say :- in an alternator before the coil even spins the magnets lines of force polarizes the two ends of the coil leaving one end of the coil positively charged and the other negatively charged, then as the coil is spun 180 degrees the electrons rush to the other side of the coil which switches the polarity? between the two terminals is where a voltage exists?
As you can probably see in my question I am finding it hard to understand each magnet poles magnets effect of the electrons in the coil, especially as both poles of the magnet are pulling towards each other how do the electrons decide which way to go in side the coil?
I'd really appreciate if you could clear this up for me in the most basic language possible.
Thanks soo much in advance
James Hawkins

James - UK



In an electrical generator, the output voltage is determined by the number of turns in the armature, the strength of the magnetic field of the poles, and how fast the coils pass through the magnetic field (RPM of the generator).

The difference between an AC and DC generator is the configuration of the armatures. See: Generating Electrical Current.

The relationship between the direction of the current and the magnetic field is sen at: Moving Electrical Charges Create Magnetic Field.

An alternator is a special configuration of a generator that is mainly used in cars, such that the speed of the engine has no effect on the voltage or current output.

I hope that helps. Best wishes in your studies.

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Changing AC to DC electricity

Topic: AC Transformers


May 18, 2013

Pls, tell me that,does a transformer can covert AC to DC?
If yes then how? pls rpl me.I need to know as soon as be possible.

Rahul - India



A transformer only changes the voltage of AC electricity. A device called a rectifier changes AC to DC on large scale. The are also called adapters when you convert AC to DC for small devices.

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Can I use 60Hz radio with 50Hz?

Topic: AC World Voltages


January 18, 2013

Can I USE 110 v / 60 cycle am fm radio on 110 v / 50 cycle without any noise destortion ?

Raojibhai - USA



One concern is that the radio made for 60Hz on 50HZ AC is that its transformer can overheat. Some people claim there is no problem, while others say you should use caution.

I would guess that there also may be some distortion on the sound.

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When atoms lose electrons.

Topic: Electrical Charges


September 30, 2012

so if an atom consist of sub-atomic particles protons, neutrons and electrons; and too many electrons in an atom make it negative or with missing electrons make it positive. Should it not need to be balanced? like equal number of protons for the same amount of electrons to have the desired reaction? What would happen beyond becoming a positive ion if an atom losses electrones what the reaction would be likewise if in contrast gains electrons?




Having the same number of electrons as protons is the most stable case for an atom. However, for atoms with only one or two electrons in the outer orbit or shell, they are only loosely held and may break away from the atom, creating a positive ion. The free electrons may then bind with another atom or move through the material as an electric current.

Atoms with the outer shell that could hold another electron may attract a free electron and become negative ions.

The loss of electrons or gain in the outer shells of atoms is the basis for chemical reactions. See Chemical Bonding for more information.

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How are transformers used to distribute electricity?

Topic: AC Transformers


September 23, 2012

1. how are transformers used in the distribution of electricity?
2.explain why mains electricity is alternating current rather than direct current?




It is much easier to change the voltage with AC electricity than with DC. Thus, voltages can be higher for long-range transmission with AC as opposed to using DC. AC transformers are used to increase the voltage for transmission and then decrease it at the homes, thus working to distribute the electricity.

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How can electrons move in a vacuum?

Topic: Electricity Basics


September 19, 2012

electrons required a medium to move,how can they in vaccum?

harsha - India



Most vacuums have a small number of atoms or ions that allow the electrons to flow. A "pure" vacuum is actually impossible.

However, vacuums--even with some atoms or ions--have a large electrical resistance that prevents electrons from moving untile the potential (voltage) is high.

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Air conditioner not running well with Guam electricity

Topic: AC World Voltages


August 8, 2012

My question is concerning Air conditioning equipment. We have units that have alot of electronics in it. They have inverter boards which convert AC to DC to control the compressor,reactor coil, Transmission boards, Active filter modules and all the other boards associated with this. This equipment is rated 208/230 50 cycles. But here on Guam we have 60 cycle power. The question is will this effect the operation of the equipment. We seem to be having alot of electronic problems

Roger - Guam



Your mechanical equipment, such as the compressor motor, will be running slower on 50Hz and thus be less effective. Also, the electronics may not be as effective because of the difference in cycles.

50Hz to 60Hz converters or inverters can be expensive. But also, the electronic problems you are having could also be expensive. Depending on the number of AC units you have and their cost, it might be better to get something suitable to the Guam power.

Best wishes on solving your problem.

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Will DC current readily flow through a conductive gas?

Topic: Electricity Basics


July 13, 2012

Will DC current readily flow through a conductive gas? Will it flow through a vacume? Do you think it is possible to use conductive gas to extract DC current from an Acylic/Homopolar generator by filling a cavity surrounding said rotor with conductive gas, and placing a conductive ring in close proximity to the equator of said rotor, and a conductor 90 deg from the equator in close proximity to the rotor's conductive axel? As it is from these two points a DC EMF is produced from the Acylic/Homopolar generator @ 2 volts DC, with a 45deg curve in amperage, directly proportional to rotational speed.

I thank you for your kind attention to my unorthodoxed questions.

Gordon - USA



A gas is conductive if it consists of a sufficient number of positive or negative ions. Thus, it allows free electrons to flow through it. This means that both DC and AC electricity will flow though a conductive gas.

Since a vacuum has few--if any--atoms, it poses a very large resistance to electrons. With sufficient voltage, electrons will jump the gap.

A homopolar generator requires a magnetic field perpendicular to a conductive disk. I'm not sure where the acrylic disc comes into play. I've seen a few websites on acrylic/homopolar devices, but I don't know how valid they are.

I hope this helps. Best wishes in your endeavor.

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Why does AC change direction twice per period?

Topic: AC


July 4, 2012

why do the alternating current chang direction 2 times per period?

vanna - Cambodia



A period in any wave motion, including AC electricity, starts in one direction, reaches a peak goes back to zero, goes in the other direction until it reaches a negative peak, and then returns to zero. That results in changing two direction per period.

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