Magnetic Properties of Matter: Practice Problem & Solution

Short Solution (Best for NEET):

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:

For an electron, the orbital angular momentum \( vec{L} \) is proportional to \( vec{r} times vec{v} \). The magnetic moment \( vec{mu} \) is \( -frac{e}{2m_e} vec{L} \). The negative sign arises because the electron is negatively charged, causing the direction of the equivalent current to be opposite to the electron's orbital motion. Thus, both A and R are true, and R correctly explains A.