Magnetic Properties of Matter: Practice Problem & Solution

Solution Explained:

To solve this problem, we apply the core principles of Magnetic Properties of Matter. Understanding the underlying formula is key to arriving at the correct answer below:

Ferromagnetic and paramagnetic materials indeed lose their specific magnetic properties upon strong heating (e.g., ferromagnets become paramagnetic above Curie temperature). So, Assertion (A) is true. However, Reason (R) is false; while diamagnetism is a universal property, most substances exhibit paramagnetism (due to unpaired electrons) or ferromagnetism, which mask diamagnetism.