A soft iron piece is in the form of a closed ring (no free ends). A wire is wound over it to make it an electromagnet. What happens when current is passed in the wire ?

1. It does not get magnetised.
2. It gets temporarily magnetised.
3. It becomes magnetised.
4. It can be magnetised if broken into two parts.

Which of the following devices does not use an electromagnet ?

1. Magnetic compass
2. Electric fan
3. Relay
4. Microphone

The figure depicting the correct magnetic field lines when the magnet is placed with its south pole pointing towards north is :

1.

2.

3.

4.

Assertion (A) : Two bar magnets attract when they are brought near to each other with the same pole.

Reason (R) : Unlike poles attract each other.

1. both A and R are true and R is the correct explanation of A
2. both A and R are true and R is not the correct explanation of A
3. assertion is false but reason is true
4. assertion is true but reason is false