The magnetic field generated by eddy currents induced in a test specimen:

The magnetic field generated by eddy currents induced in a test specimen works according to Lenz's Law, which states that the direction of an induced current is such that it opposes the change that caused it. When an alternating magnetic field is applied to a conductive material, eddy currents are induced within the material. These eddy currents then generate their own magnetic fields that are oriented in the opposite direction to the original magnetic field that created them.

This opposition is crucial for various applications, including non-destructive testing techniques, where understanding the behavior of eddy currents can help in assessing material properties and detecting flaws. Recognizing that the induced magnetic field counteracts the inducing field is fundamental in analyzing and interpreting eddy current tests.

Other options do not align with Lenz's Law. For instance, suggesting that the induced magnetic field reinforces or cancels the inducing field would contradict the principle that induced effects resist changes in the system. Similarly, stating that it has no effect overlooks the significant role that the opposing induced magnetic field plays in the dynamics of the eddy currents and the overall electromagnetic interaction.