What is the formula used to calculate the inductive reactance of a test coil?

The formula to calculate the inductive reactance of a test coil is given by (X = 2\pi f L), where (X) represents the inductive reactance in ohms, (f) is the frequency in hertz, and (L) is the inductance in henries.

In the choice provided, although it appears without the 'pi' symbol, the interpretation of (2nl) can be taken to symbolize the relationship of frequency and inductance, which establishes the foundational concept of inductive reactance. Both frequency (which is often denoted by (f) and can relate to 'n' as a factor of cycles) and inductance ((L) represented as 'l' in the context of this question) combine to define how much opposition a test coil will provide to alternating current.

This relationship is critical in understanding how a test coil behaves in an electromagnetic field, especially in nondestructive testing applications where inductive measurements are used. By recognizing that inductive reactance is affected by both the frequency of the input signal and the coil's inductance, one can manipulate these parameters to achieve desired results in testing scenarios.