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Feedback Comments on Electricity

by Ron Kurtus

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

You can read them to further your understanding of the subject.

List of next 10 letters




DC Electromotive force and potential difference Pakistan
Generating Electricity Explain the working principle of a transformer Nigeria
General Difference between electrical and electronics USA
AC This is a really awesome and informative site USA
DC Wants more questions India
DC Circuits How is parallel circuit different than series circuit? USA
Electrical Charges What is Electricity? India
DC Using a ground wire to light a lamp with AC USA
AC What is the purpose of the neutral wire in a circuit Pakistan
AC How does a 220 volt AC baseboard heater work? USA

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First 10 letters

Electromotive force and potential difference

Topic: DC


May 2, 2012

define electromotive force and potential difference?

muneeb - Pakistan



Electromotive force (emf) is the voltage created by a battery or DC generator. It is not considered a true "force".

Electrical potential difference is the voltage difference between two points, such as between the terminals in a battery. It is equal to the work needed to move a unit charge between the two points.

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Explain the working principle of a transformer

Topic: Generating Electricity


March 18, 2012

explain the working principle of a tranformer

feminton - Nigeria



See Alternating Current (AC) Transformers for an explanation with a picture.

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Difference between electrical and electronics

Topic: General


March 18, 2012

What is the difference between ELECTRICAL and ELECTRONICS?




Electrical usually concerns electrons flowing through a wire. It can be either AC or DC electricity and it used to power various devices.

Electronics concerns using the movement of electrons in electrical circuits to control the flow of information, as well as to process signals. Transistors and integrated circuits can be used to amplify weak electrical signals, as well as to count and calculate information from the input.

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This is a really awesome and informative site

Topic: AC


February 21, 2012

This is a really awesome and informative site. Thank you!

Ti - USA



thanks for the feedback. I'm glad the site has been useful to you. Best wishes for success in your studies.

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Wants more questions

Topic: DC


January 26, 2012

want more questions relating to this chapter?

Lathika - India



We should be adding more questions in the near future.

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How is parallel circuit different than series circuit?

Topic: DC Circuits


January 25, 2012

i didn't understand how a parallel circuit is wired different than a series circuit.can you explain?

ignacio - USA



The illustrations in Direct Current (DC) Electrical Circuits shows how a series circuit has its resistors in a line, one after another, while a parallel circuit has the resistors going across the circuit but parallel to each other.

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What is Electricity?

Topic: Electrical Charges


January 14, 2012

What is Electricity ?

Atish - India



Static electricity is the collection of electrical charges on the surface of a non-conducting material. AC and DC electricity is the movement of electrons through a conducting material, like copper wire.

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Using a ground wire to light a lamp with AC

Topic: DC


November 30, 2011

Using a light with two wires, and I touch a AC power sourse on one side and touch a earth ground on the other side the lamp will light up. If I use a DC power sourse (battery charger) and touch touch one side (hot) and touch a earth ground on the other side the lamp will not lite. Why?

Rodger - USA



You need a complete circuit for the power source to light the lamp. With a DC source, you would normally connect wires from the positive (+) and negative (-) terminals to the lamp. But you could connect one wire from the DC source to the ground and another wire from the ground to the lamp. However, it would depend on the resistance of the ground.

With AC, ground often splits the voltage. If part of the AC circuit has been grounded, then when you use a wire to ground with your lamp, the circuit is then completed. It is sort of an unusual situation.

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What is the purpose of the neutral wire in a circuit

Topic: AC


November 24, 2011

what is neutral and its purpose or current flow in a circuit?

usman - Pakistan



In a 3-wire AC system, the neutral is the zero point between the other two wires. It is often connected to the ground or earth wire, as a way to protect against added DC voltages.

In the U.S., 220 VAC comes to the house, but only half of the voltage is used, with a hot wire and the common or neutral wire. This allows both 110 VAC and 220 VAC to be used in the house. Most countries don't use that system.

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How does a 220 volt AC baseboard heater work?

Topic: AC


November 17, 2011

How does a AC 220 volt baseboard heater work ? Do not understand how putting 110 in one end and 110 in the other end can make it work, How does the circut get completed? Also why are earthworms not getting shocked when power is passing to your home grounding rod.
Thank You

Willie - USA



US house current is usually 220 VAC but is split to become 100 VAC with respect to the common or ground. Although the black wire is considered hot, the white also has AC with respect to the common or ground. A typical way to wire a 220 V heater is to use the black and white wires and not use the ground.

Grounding is mainly used to have a common zero point for DC. Often AC circuits have a floating DC component, which could shock a person. However, touching a grounded wire will not give you a shock, as long as you aren't touching metal that has a voltage.
Although worms are attracted to grounding rods, they would need to be in contact with a DC or AC wire to have the current go through them and give them a shock.

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