What happens to the magnetic field strength produced by a circular coil if the number of turns (n) is increased while keeping the current constant?

Correct option is C

The correct answer is (c) It becomes n times larger than for a single turn.

Explanation:
• According to electromagnetism, the magnetic field produced by any current-carrying wire at a specific spatial point depends directly on the magnitude of the current passing through it.
• In a tightly wound circular coil containing precisely n turns, the electrical current within each individual circular turn flows in the exact same direction.
• Because the current direction is uniform, the individual magnetic field vectors produced by each distinct turn add up constructively at the center.
• Therefore, the total resulting magnetic field becomes mathematically n times as large as the field produced by just a single isolated turn.
• Mathematically expressed, the generated magnetic field $B$ is directly and linearly proportional to the total number of turns $n$.

Information Booster:
• The overall strength of this magnetic field can also be dynamically increased if the magnitude of the electric current passing through the wire is artificially increased.
• Conversely, the magnetic field strength at the center is strictly inversely proportional to the radius of the circular coil.

Additional Knowledge:
It remains the same as for a single turn. (Option a)
• This conceptual statement is incorrect; the individual magnetic fields from multiple turns reliably reinforce each other to create a stronger net field.

It decreases inversely with n. (Option b)
• This statement is completely backward; physically increasing the number of turns increases the overall field strength, rather than decreasing it.

It only increases if the diameter is also increased. (Option d)
• This statement is kinematically incorrect; physically increasing the diameter of the coil actually decreases the measured field strength at the exact center of the coil.

So the correct answer is (c)