Physics
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.
Answer
option 1
Reason —
Options (1) and (3) are correct : Here field lines go from north to south direction outside the magnet which matches the physical rule of magnetic field direction i.e., magnetic field lines originates from north pole and terminate at south pole outside the magnet.
Option (2) is incorrect : As field lines are going from S to N outside the magnet which is opposite of correct magnetic field line direction.
Option (4) is incorrect : Some field lines are coming from north to south while some are going from south to north forming a closed loop outside the magent but magnetic field lines always move from north to south direction outside the magnet.
Related Questions
Which of the following devices does not use an electromagnet ?
- Magnetic compass
- Electric fan
- Relay
- Microphone
The magnetic polarity at the two ends of a horse-shoe magnet depends on :
- the strength of current in the coil
- the number of turns in the coil
- the material on which the coil is wound
- the direction of current at the ends of the magnet.
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.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false
Assertion (A) : Strength of an electromagnet can be increased by increasing the number of turns of winding on solenoid.
Reason (R) : Magnetic field strength is directly proportional to number of turns on the solenoid.
- both A and R are true and R is the correct explanation of A
- both A and R are true and R is not the correct explanation of A
- assertion is false but reason is true
- assertion is true but reason is false