Tag: electric charges and fields

Questions Related to electric charges and fields

From below which is the example of insulators.

physics electric charges and fields conductors and insulators introduction to electrostatics electricity

  1. Metallic elements

  2. Non Metallic elements

  3. graphite

  4. acqueous solution of salt

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Correct Option: B
Explanation:

Metallic elements have free electrons on the metallic surface and thus they are extremely good conductors. 


Graphite is a good conductor of electricity because its electrons are delocalized or free to move around. Graphite is structured into planes with tightly bound atoms. There is a great deal of distance between planes, and they are bonded weakly together, allowing the electrons to move around.

When a salt is added in water, it dissociates into respective ions and these collect on the cathode and anodes respectively and a current is maintained. 
Hence it is a conductor.

The materials that do not allow flow of electron through them are known as :

physics electric charges and fields conductors and insulators introduction to electrostatics electricity

  1. conductors

  2. insulators

  3. semi conductors

  4. electrolytes

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Correct Option: B
Explanation:

The materials that do not allow flow of electron through them are known as Insulators.


Option B is correct.

State whether given statement is True or False :

In conductors electric current can flow freely. 

physics electric charges and fields conductors and insulators introduction to electrostatics electricity

  1. True

  2. False

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Correct Option: A
Explanation:

True

In conductors electric current can flow freely.

Option A is correct.

Until when does the charged particle transmits charge to other?

physics electric charges and fields conductors and insulators introduction to electrostatics electricity

  1. Until the overall repulsive forces between electrons is minimised.

  2. Until the overall repulsive forces between electrons is maxmised.

  3. Until the overall repulsive forces between electrons is become neutral.

  4. None

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Correct Option: A
Explanation:

Until the overall repulsive forces between electrons is minimised, the charged particle continues to transmit charge to other particles.


Option A is correct.

Electrical charge can be transferred from a charged object to another through

physics electric charges and fields conductors and insulators introduction to electrostatics electricity

  1. vacuum

  2. air

  3. insulator

  4. conductor

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Correct Option: D
Explanation:

We know that a conductor has free electrons and due to this, the conductor is able to transfer electric charge (the current).  

Earthing is provided in buildings to protect it form

physics electric charges and fields conductors and insulators introduction to electrostatics electricity

  1. lightning

  2. leakage of electric current

  3. cyclone

  4. thunderstorm

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Correct Option: B
Explanation:

Earthing means to connect electrical system to earth or soil in such a manner as it ensures an immediate discharge of electrical energy night out any danger. it is essentially done to product the building from any miss happening.

Ordinary rubber is an insulator. But the special rubber tyres of aircrafts are made slightly conducting. Why is this necessary?

physics electric charges and fields conductors and insulators introduction to electrostatics electricity

  1. The charged developed due to atmospheric electricity finds its way to the earth

  2. The charged developed due to friction finds its way to the earth

  3. The charged developed due to induction finds its way to the earth

  4. The charged developed due to the aircraft engine finds its way to the earth

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Correct Option: B
Explanation:

Ordinary rubber is an insulator. But the special rubber tyres of aircrafts are made slightly conducting. This is because during landing or takeoff, the tyres of aircrafts get charged due to friction between tyres and the ground. In such case, the tyres are slightly conducting, the charges developed on the tyres will not stay on them and find its way to earth.

__________ is a good conductor of electricity.

physics electric charges and fields conductors and insulators introduction to electrostatics electricity

  1. Iodine

  2. Graphite

  3. Sulphur

  4. Bromine

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Correct Option: B
Explanation:

Non-metals are the bad conductor of electricity except one i.e Graphite(made of carbon).Hence iodine,sulphur and bromine do not conduct electricity.

State whether true or false:
Alcohol and ether are conducting liquids of electricity. 

physics electric charges and fields conductors and insulators introduction to electrostatics electricity

  1. True

  2. False

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Correct Option: A
Explanation:


Ionic Liquids like alcohol and ether frequently share a number of attractive properties that distinguish them from conventional organic solvents, such as low (and even effectively-null) vapor pressure, a wide liquid range, low flammability, high conductivity (e.g., ionic, thermal), excellent stability (e.g., thermal, chemical, redox, radiochemical), a wide electrochemical potential window, and the ability to act as surprisingly good solvents towards many substances.
Ionic Liquids are a new class of purely ionic, salt-like materials that are liquid at unusually low temperatures.
Hence, the statement is true.

State whether true or false :

A piece of fresh potato does not conduct electricity at all.

physics electric charges and fields conductors and insulators introduction to electrostatics electricity

  1. True

  2. False

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Correct Option: B
Explanation:

False.

A potato has the potential to conduct electricity because it is a source filled with electrolytes. These electrolytes act as an electrical conductor which means they allow the flow of electric charges.thus it will conduct electricity.