Electro Magnet

Q. Pick the safety device used in domestic electric circuits.

1. MCB
2. Battery
3. Switch
4. CFL

Q. Electromagnets can be used to lift heavy loads.

1. True
2. False

Q. Does electromagnet have South pole & North Pole?

Q. Consider the below circuit diagram.

Which of the following bulbs would glow, when the switch is in its OFF position?

1. Bulb A
2. Bulbs B and C
3. All the bulbs would glow
4. None of the bulbs would glow

Q. Explain electromagnet with a diagram. [5 MARKS]

Q. Electromagets are used in ______.

1. speakers
2. metal detectors
3. hard drives
4. food industry

Q.

In certain applications, electromagnets are better than permanent magnets because:
(more than one answers can be correct)

1. Electromagnets do not require electricity.

2. The strength of the magnetic field of an electromagnet can be controlled.

3. The polarity of an electromagnet can be reversed.

4. Electromagnets can be made to act as a magnet when needed.

Q. Which of the following statements is NOT true about an electromagnet?

1. It works only in the presence of electricity.
2. It is a permanent magnet.
3. An insulated wire is wound around it.
4. It is used in fans and radios.

Q.

Which of the following is/are true with respect to electromagnets?

1. Magnetic properties remain as long as the current flows.

2. Its magnetic strength is fixed.

3. The magnetic properties are permanent.

4. It does not have poles.

Q.

Working of an electromagnet is based on ___.

1. Heating effect of electric current

2. Electro-chemical effect of electric current

3. Magnetic effect of electric current

4. Chemical effect of electric current

Q. Sort the magnetic strength of electromagnet in ascending order from top to bottom when current is varying.

1. Current = 1 A
2. Current = 3 A
3. Current = 6 A
4. Current = 8 A
5. Current = 12 A

Q.

The following arrangement will behave as an electromagnet.

1. True

2. False

Q. Which of the following is not true about electromagnets?

1. The magnetic property is caused due to the flowing current.
2. Electromagnets are temporary magnets.
3. The magnetic strength cannot be changed.
4. Poles can be interchanged.

Q.

Which of the following is/are true with respect to electromagnets?

1. It does not have poles.

2. Magnetic properties remain as long as the current flows.

3. Its magnetic strength is fixed.

4. The magnetic properties are permanent.

Q. Electromagnets are necessarily strong magnets.

1. True
2. False

Q. State two important uses of electromagnets.