Electricity and Magnetism MCQ question and answer with solution | Physics Gk MCQs

The correct answer is Option A: They can emanate from a point.
Here's why:
Magnetic field lines are a way to visualize magnetic fields.
Let's break down each option:
Option A: They can emanate from a point - This is incorrect.
Magnetic field lines always form closed loops.
They don't just start or end at a single point.
They emerge from the north pole of a magnet and enter the south pole, continuing *inside* the magnet to complete the loop.
Option B: They do not cross each other - This is correct.
If magnetic field lines crossed, it would mean that at that point, the magnetic field would have two different directions simultaneously, which is impossible.
Option C: Field lines between two poles cannot be precisely straight lines at the ends - This is correct.
Field lines are only straight in the very center of the space between two opposite poles.
At the ends, they curve to connect back to the magnet.
Option D: There are no field lines within a bar magnet - This is incorrect.
As mentioned earlier, magnetic field lines form closed loops.
They continue inside the magnet, going from the south pole to the north pole.