If the conductivity of a test part decreases, what happens to the magnitude of eddy currents?

When the conductivity of a test part decreases, the magnitude of eddy currents decreases as well. This phenomenon is based on the relationship between conductivity and the ability of a material to support the flow of electric current.

Eddy currents are generated when a changing magnetic field induces circulating currents within a conductor. The strength and magnitude of these currents are directly related to the material's conductivity. A more conductive material allows for greater movement of electrons, resulting in stronger eddy currents. Conversely, when the conductivity is reduced, the material offers more resistance to the flow of these currents. This increased resistance hinders the establishment and intensity of the eddy currents, leading to a decrease in their magnitude.

Thus, as the conductivity of a test part decreases, the resulting eddy currents become weaker, aligning with the provided answer.