Diamagnetism — Prelims Strategy

Prelims Strategy

To tackle NEET questions on diamagnetism effectively, focus on conceptual clarity and precise recall of properties. Firstly, understand that diamagnetism is universal and induced, arising from Lenz's Law, leading to opposition.

Memorize the key properties: weak repulsion, negative and small magnetic susceptibility ($\chi < 0$), relative permeability slightly less than 1 ($\mu_r < 1$), and crucial temperature independence. Practice identifying common diamagnetic examples like water, copper, and bismuth.

For numerical problems, these are usually straightforward applications of $\mu_r = 1 + \chi$. Pay close attention to the sign of susceptibility. When comparing with paramagnetism, remember diamagnetism is about repulsion and temperature independence, while paramagnetism is about attraction and temperature dependence (Curie's Law).

Trap options often involve confusing these properties or misidentifying materials. Always read the question carefully to determine if it asks for a correct or incorrect statement, or to identify a specific type of material.