Earthing

Q.

What is an earth electrode?

1. electrode connected to the circuit

2. electrode which is connected to the mains

3. material used for earthing

4. electrode which is connected to earth

Q.

To which wire is the metallic case of an electric appliance connected? Give the reason.

Q.

What is meant by short circuit

Q.

Explain why a charged body loses its charge if we touch it with our hand.

Q. What is the main purpose of earthing electrical appliances?

1. To present overloading
2. To present short circuting
3. To prevent the person form electric shock
4. None of these

Q.

(a) The earthing of an electric appliance is useful only if the fuse is in the live wire. Give the reason.

(b) Name the part of the appliance which is earthed.

Q.

The death of a person caused by electric shock when electric current passes through the body is called ____________.

Q.

What is the function of an earth wire ? Why is it necessary to earth the metallic bodies of electrical appliances ?

Q.

In household wiring, which 2 wires have the same potential?

Q.

In a three-pin plug, the pin made longer and thicker than the other two pins is

1. Neutral Pin

2. Earthing Pin

3. Fuse Pin

4. Live Pin

Q. The potential difference between live wire and neutral wire is

1. $100V$
2. $200V$
3. $50V$
4. None of these

Q. In a three-pin plug, why is the earth pin made longer and thicker than the other two pins?

Q. What is the function of earth wire in electrical instruments ? Why is it necessary to earth the metallic electric appliances.

Q.

The thickest pin in an electrical plug corresponds to ___ pin.

Q. Why is earthing required?

Q.

We do not receive any electric shock due to the earth connection.

1. True
2. False

Q. Many electrical appliances are earthed or grounded. Reason behind this

1. to make electricity balance
2. due to "g"
3. all
4. protection against shock

Q. Earthing is provided in buildings to protect it from:

1. lightning.
2. thunderstorm.
3. cyclone.
4. leakage of electric current.

Q. Question 12
The most important safety method used for protecting home appliances from short circuiting or overloading is

(a) earthing
(b) use of fuse
(c) use of stabilizers
(d) use of electric meter​​​​​​​

Q.

What is an earth electrode?

1. Electrode connected to the circuit

2. Electrode used for earthing

3. Electrode which is connected to the mains

4. Electrode which reduces current flow

Q. What do you mean by electric shock? Explain how it takes place?

Q. If the insulation of live wire got damages and the live wire comes in contact with the metallic body of the appliance. When such electric appliance is connected to the mains, if not connected to the earth wire will also be raised to

1. $440V$
2. $110V$
3. $220V$
4. $600V$

Q.

The colour of earth wire is:

1. Black
2. Blue
3. Red
4. Green

Q.

Of the three connecting wires in a household circuit, two of the three wires are at the same potential. They are:

1. Live and Earthing Wires

2. Live and Neutral Wires

3. Earthing and Neutral Wires

4. Earthing and Fuse Wires

Q. What is electric shock?

Q.
Two types of earthings are provided: (a) Equipment earthing and (b) Neutral point earthing. Equipment earthing is provided for

1. Safety of human being
2. Safety of equipments
3. Safety of starters and cables
4. None

Q. We know that earth is an electron bank and that it has zero potential. But quite often we get electric shock from computer despite proper earthing.
Proper earthing will give us safety from electric shock. What is meant by proper earthing ? How can the earthing arrangement by done properly to ensure safety ?

Q. If a person touches the appliance, his body provides a path for current to flow to earth which is at ............ potential.

1. Infinite
2. high
3. low
4. zero

Q. What is the main propose of earthing an electrical appliance?

Q. Define the terms Electro-typing and Electro-plating.