Question

The quantum numbers $+\frac{1}{2}$ and $-\frac{1}{2}$ for the electron spin represent

• A. Rotation of the electron in clockwise and anti-clockwise directions, respectively
• B. Rotation of the electron in anti-clockwise and clockwise directions, respectively
• C. Magnetic moment of the electron pointing up and down, respectively
• D. Two quantum mechanical spin states which have no classical analogue

Answer 1

The correct option is D

Two quantum mechanical spin states which have no classical analogue

Always keep in mind,
$S=+\frac{1}{2}$ and $S=-\frac{1}{2}$ does not mean they are rotating clockwise-anticlockwise, pointing up and down etc.
These are two quantum mechanical spin states which has no classical analogue.