Tag: physics

Questions Related to physics

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

  1. conductors

  2. insulators

  3. semi conductors

  4. electrolytes


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. 

  1. True

  2. False


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?

  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


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

  1. vacuum

  2. air

  3. insulator

  4. conductor


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

  1. lightning

  2. leakage of electric current

  3. cyclone

  4. thunderstorm


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?

  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


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.

  1. Iodine

  2. Graphite

  3. Sulphur

  4. Bromine


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. 

  1. True

  2. False


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.

  1. True

  2. False


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.

State whether true or false :

Rain water is a non-conductor of electricity.

  1. True

  2. False


Correct Option: B
Explanation:

False.

Rain water is a conductor of electricity due to The most common one is carbon dioxide. Carbon dioxide itself in not an electrolyte, but it reacts with water to make what is often called "carbonic acid". Carbonic acid is actually a fictitious acid, since there are no molecules of ${H} _{2}{CO} _{3}$ in aqueous solution. But what is present that makes rain water a conductor are $H^+$ and $HCO^{3-}$ ions. 

$CO _2$(aq) $+$ $H _2O$(l) <==> $H^+$ $+$ $HCO^{3-}$ 

$1000$ years ago, that would have pretty much been it. But today we have lots more pollutants in the air that contribute to acid rain and to the conductivity of rainwater. $SO _3$ dissolves in water to make $H _2SO _4$, which exists as $H^+$ and $HSO^{4-}$ ions. $N _2O _5$ dissolves in water to make $HNO _3$, which exists in water as $H^+$ and $NO^{3-}$. These are but a few of the substances that can produce the ions in solution that will make rainwater a conductor.