Magnetic field is a quantity that has _ _ _ _ . The magnetic field lines emerge from _ _ _ _ _ pole and merge at _ _ _ _ pole.

(A) Only magnitude, north, south.

(B) Only magnitude, south, north.

(C) Both magnitude and direction, south, north.

(D)Both magnitude and direction, north, south.

Magnetic field is a vector. A vector has magnitude and direction (shown by an arrow whose length ∝ magnitude and whose direction matches the quantity). Thus, a magnetic field has both magnitude and direction.

Direction of magnetic field

By convention, it’s the direction a north pole of a compass would move. Field lines go from North to South outside a magnet and from South to North inside, forming closed curves.

Key features of magnetic field lines

1. Closed loops: run from N → S outside, and S → N inside the magnet.
2. Never intersect: two directions at one point is impossible.
3. Density ∝ strength: lines are closer where the field is stronger, sparser where it’s weaker.
4. Tangent gives direction: at any point, the tangent to a line shows the field’s direction.
5. No physical flow: lines are a conceptual tool, not moving entities.

Hence, Option (D) is the correct answer.