Electric Fuse

Q. Question 23
How does use of a fuse wire protect electrical appliances?

Q.

Name the material which is used as a fuse wire?

Q. 'X' is a safety device used in electrical circuits which prevents damage to electrical equipments. Identify 'X':

1. Electromagnet
2. Fuse
3. Electric cell
4. Tubelight

Q.

Why Cu, Al are used over tungsten, Fe Ni to make fuses?

1. Fe, Ni are costly

2. Cu is a bad conductor

3. They are cheap

4. They have low melting point

Q. Fuses are always connected in series with the live wire.

1. False
2. True

Q. Identify the part which acts as fuse in the given circuit:

1. 
2. 
3. 
4. 

Q. An electric fuse works on the principle of Joule's law of heating.

1. False
2. True

Q. For a fuse rated at 10 A, the fuse melts if the current in the circuit exceeds A.

1. 5
2. 10
3. 1
4. 100

Q. Tungsten is not an ideal material for making fuse.

1. False
2. True

Q. An electrician is carrying out some repairs in your house. He wants to replace a fuse by a piece of wire. Would you agree? Give reasons for your response.

Q. For a fuse rated at 10 A, the fuse melts if the current in the circuit exceeds ___________.​

Q.

What does a 5 A rating on a fuse mean?

1. Burns down if I < 5 A

2. Melts if I > 5 A

3. Can function only if I = 5 A

4. Does not indicate anything

Q. The material used in making the wire of an electric fuse should have a high melting point.

1. False
2. True

Q. In which of the following cases, the fuse operates to break the circuit?

1. Underloading
2. (b) and (c) above.
3. Overloading
4. Short circuit

Q.

Which of the following is used as a safety device?

1. Switch

2. Battery

3. Filament

4. Fuse

Q. The working of electric fuse is based on:

1. Ohm’s law
2. Joule’s law of heating
3. Coulomb’s law
4. Faraday’s law