Magnetic Moment and Angular Momentum of Electron – Rankers Physics

Magnetic Properties of Matter: Practice Problem & Solution

Assertion (A): The direction of magnetic moment and orbital angular momentum are opposite to each other for electron. Reason (R): Electron is negatively charged.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

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:

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.

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Similar Practice Questions

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