The ratio of a field produced due to a current carrying circular coil of n turns, to that of a field produced due to a single circular loop of the same radius carrying the same current is:

Correct option is B

The correct answer is (b) n:1.

Given:
A circular coil of n turns and a single circular loop.
Solution:
To find the ratio of the field is due to both coil and circular loop.
No of turns in the circular coil is n.
No of turns in the single loop is 1.
As the magnetic field is directly proportional to the number of turns we have:

​$$\frac{No\ of\ turns\ in \ coil}{No\ of \ turns\ in\ single\ loop}= \frac{n}{1}$$

So, the ratio of the field is n:1​​