Question

Which of the compass needle orientations in the following diagram correctly describes the magnets field at that point?

Answer 1

Hint: For solving this question we must remember the direction of flow of magnetic field lines. We know that the lines flow from North to South direction.

Complete step-by-step answer:
A magnetic field is observed near the magnets where we can observe the magnetic fields. It is a vector quantity. These fields are also observed near the electric charge as we know that near these charges the force of magnetism is observed. The unit of magnetic field is given in Tesla and it is represented by B or H. Magnetic field lines describe the magnetic force on the north monopole at any given point.
One of the most important points to note is that the density of these lines indicates the magnitude of the magnetic field. We may have noticed that the magnetic field is strongest near the pole and it becomes weak as we move against the poles.
It appears that these lines come out from the north pole and enter into the south pole.

Magnetic field lines diagram.

In our given question we can see from the option that
Compass B, C and D does not indicate the lines that are coming out or going in through the poles as indicated in the magnetic field diagram. But we can see that option A indicated the direction of magnetic field lines coming out from North poles.
Hence the compass A is the correct answer as the magnetic field of a bar magnet passes from North to South direction.

Note: For solving these types of questions we must remember the definition of magnetic field lines. A magnetic compass is a very important device which is used to show the density of magnetic field and flow of direction of the field. So, we must always remember this property.