Question

The angle made by electron's orbital angular momentum (\(L\)) with the direction of the orbital magnetic moment (\(M\)) is

• A. \(120^{\circ }\)
• B. \(60^{\circ }\)
• C. \(180^{\circ }\)
• D. \(90^{\circ }\)

Hint:

The electron is negatively charged, so its magnetic moment points opposite to its orbital angular momentum.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept
The orbital magnetic moment of an electron is \(\vec{M}=-\dfrac{e}{2m}\vec{L}\).

Step 2: Direction
The negative sign shows that \(\vec{M}\) is directed opposite to \(\vec{L}\), because the electron carries negative charge.

Step 3: Angle
Two antiparallel vectors make an angle of \(180^{\circ}\).

Step 4: Compare the options
This matches option (C).

Final Answer:
The angle between L and M is 180 degrees. \[ \boxed{\text{(C) }180^{\circ}} \]