Magnetic Particle Inspection Level 2 Practice Exam

Materials that are repelled magnetically are known as which of the following?

1. Paramagnetic

2. Diamagnetic

3. Ferromagnetic

4. Nonmagnetic

The correct answer is: Diamagnetic

Materials that are repelled magnetically are classified as diamagnetic. This phenomenon occurs because diamagnetic materials have no unpaired electrons, leading to the absence of permanent magnetic moments. When exposed to an external magnetic field, these materials induce a magnetic field in the opposite direction, causing them to be repelled by the external source. While paramagnetic materials also contain unpaired electrons, they are weakly attracted to magnetic fields rather than repelled. Ferromagnetic materials display strong attraction to magnetic fields due to their unpaired electrons and the ability to retain magnetic polarization. Nonmagnetic materials are those that do not exhibit magnetic properties in the presence of a magnetic field; however, they do not specifically demonstrate the repulsion characteristic of diamagnetic materials. Thus, the distinguishing property of diamagnetic materials is their tendency to be repelled in the presence of a magnetic field.