Physics
In the presence of earth's magnetic field, a compass needle rests in …………… direction.
- north-west
- north-east
- north-south
- east-west
Answer
north-south
Reason — The Earth's magnetic field aligns roughly with the geographic north-south axis. Therefore, when a compass needle is influenced by the Earth's magnetic field, it aligns itself with the magnetic field lines, pointing towards the Earth's magnetic north pole, which is approximately aligned with the geographic north pole. This causes the north end of the compass needle to point towards the geographic north pole, and the south end to point towards the geographic south pole, resulting in the needle resting in the north-south direction.
Related Questions
In the figure given below, when the key is pressed, a current passes in the wire in the direction from A to B (i.e., from south to north). The north pole of the compass needle will deflect towards:
- East
- North
- South
- West
The strength of a magnetic field depends on :
- magnitude of current
- direction of current
- both (1) and (2)
- none of the above
The presence of a magnetic field at a point can be detected by means of a:
- a strong magnet
- a solenoid
- a compass needle
- a current carrying wire.
In the figure given below, current is passed in a downward direction through a cardboard. The magnetic field lines would be :
- straight lines
- concentric circles
- elliptical lines
- squares