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Answers to Readers' Questions on Physical Science:

Electricity Basics

The following 8 comments and questions have been sent in. They are listed according to date.

List of first 10 items

• Why does water hold electricity?
• In which direction does electricity flow?
• What making opposite charges attract in electicity?
• Powerful charge found in a rice puller device
• Difference between dc and ac?
• Which type of electric current is more dnagerous?
• Why can't static charges be on a copper rod?
• Where is the magnetism strongest?

Next 10

Why does water hold electricity?

Question

May 7, 2010

Why does water hold electricity and attract it. Please give me the answer in terms of atoms. Thank you.

Brayden - USA

19676

Answer

Pure water does not conduct electricity. When there is even a small amount of salt in the water, (+) and (-) ions are formed, such that electricity will pass through the water. An ion is an atom with an excess of electrical charges.

Static electricity can attract a neutral materiel such as water.

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In which direction does electricity flow?

Question

April 18, 2010

In which direction does electricity flow in a circuit? Since electricity is defined in many books as the flow of electrons, I thought that electricity flow from the positive terminal to the negative terminal of a battery by first going trough the entire circuit. Then I read that before they discover the electron, scientists believed that electricity flow from positive to negative. So, I'm confuse with the answer here. Can you help me please.

Thank You

I appreciate what you do.

danny - USA

19557

Answer

By convention, electricity flows from the positive (+) to the negative (-) terminals. That was decided on years ago before they had defined an electron as having a negative (-) charge.

In reality, the flow of electrons goes toward the positive terminal. However, since they had decided on (+) to (-), circuit designs show the flow in the opposite direction of the electron movement.

It can be confusion and is a little stupid, but it is just something you need to remember.

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What making opposite charges attract in electicity?

Question

March 15, 2010

PLEASE GIVE THE INNER CONFIGURATION OF THE ATOMS THAT MAKES THE OPPOSITE CHARGES TO ATTRACT?HOW WILL BE THE INNER CONFIGURATION OF THE ATOMS WHEN THE OPPOSITE POLES ARE CREATED&THEY MADE TO BE ATTRACTED?

K PRANEETH - India

19373

Answer

Free electrons in electricity have a negative (-) charge.

The nucleus of an atom consists of positive (+) charged protons, as well as neutrons. The atom has the same number of electrons, making the atom electrically neutral.

However, if the atom is missing some electrons, it will be an ion of positive (+) charge. Free electrons will be attracted to these ions, hoping to attach and make the atom neutral again.

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Powerful charge found in a rice puller device

Question

March 4, 2010

Hi,

My mail is regarding a very powerful charge that i had found in a object and there is nobody to explain this charge.This charge can be found in many objects and metals.If an object posess this charge then the object is known as rice puller.The object can pull rice from a specified range(i have heard maximum of 20 inches).This object is brought by many companies outside india.A company which posses the license to buy rp shall pay a maximum of 1450 crore rupees(1 crore= 10 million)for an inch of that object(an inch means the rp can pull the rice from 1 inch).If the rp is original then the rice shall go to it like how a snake moves and changes its color to green then to brown and finally to black and becomes powder when it hits the object.If the rp is a fake also called as dp then the rice goes straight and hits the object while turning straight to black and becomes powder,i have certain company to buy a fake rp.The fake one shall be paid about 50 -80 lakhs for one inch.The fake rp is created by appling some electricity and then adding chemicals(i dont really know).As i surfed the net i had found that there is no such thing,but i know that is not true because i had seen an rp and im goin to finish the deal in a week,but i would really like to know why are the companies paying such a high price for just some type of static charge.A rp shall only be carried in a package of carbonpapers,sponge,papers and cotton etc.It is anti electric(not sure),because my phone doesen work in the rage of the rp if it is not protected.When a torch of battery(not rechargable,the normal small ones)is switched on and pointed to the unprotected rp then the torch goes off,while getting damaged.If the object ever comes to contact with a metal then the power goes.The object becomes as useless or useful as before.It is said to be made after the object is hit by lighting,but none can prove.

I would like to know how the object is made and what is it used for,
and please do explain the process that goes inside the atoms.

Please do reply me,
Thank you

liveinmezzy - India

19326

Answer

There have been people selling rice-pullers that are made of copper or copper iridium material. Unfortunately, it seems to be a fraud that some people are trying to sell.

However, a strong static electric charge can attract lightweight object such as rice husks from several inches away. Those electric charges can also damage electronic devices. See:
http://www.school-for-champions.com/science/static.htm

Do not bother to purchase a rice puller, though, because it is probably a waste of money.

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Difference between dc and ac?

Question

June 19, 2009

hey there can u please help me to find the difference between dc and ac and the explanation of both REPLY PLEASE SIR..

chokwe - South Africa

17925

Answer

Direct current electricity (DC) usually comes from batteries and flows in one direction in a wire. Alternating current electricity (AC) moves back and forth in a wire. Both will light a light bulb, but AC is required for many electronic devices.

See our lessons at:
http://www.school-for-champions.com/science/dc.htm
http://www.school-for-champions.com/science/ac.htm

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Which type of electric current is more dnagerous?

Question

April 18, 2009

which of the two currents AC or DC is more dangerous and why?

Neelam - India

17629

Answer

If a person would touch a high voltage AC wire, he might quickly drop it after getting a shock. But if it was a high voltage DC wire, his muscles would tense and he could not drop the wire. Thus DC is more dangerous.

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Why can't static charges be on a copper rod?

Question

July 8, 2008

Why charge (static charge) can not be developed on copper rod ?

subash - India

16191

Answer

Copper can collect negative electrical charges. See:
http://www.school-for-champions.com/science/static_materials.htm

But since copper is a conductor of electricity, the charges are quickly dissipated. A non-conductor of electricity will keep static charges on its surface.

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Where is the magnetism strongest?

Question

May 31, 2008

1) I just wanted to know that where is the magnetic strongest effect of a magnet strongest?
2)how is magnetic poles labeled?
3)what are the properties that magnet have?
4)and how is Earth like a bar magnet?

Irene - USA

16017

Answer

The magnetic effect is the strongest right at the end or pole of the magnet.

Read out lessons on magnets for more information: http://www.school-for-champions.com/science/magnetism.htm

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