MCQ
The photoelectric threshold wavelength for potassium (work function being $2eV$) is ........... $nm$
- A$310 $
- ✓$620 $
- C$1200 $
- D$2100 $
✓
Answer
Correct option: B.
$620 $
b
(b) $\lambda = \frac{{12375}}{{{W_0}}} = \frac{{12375}}{2} = 6187.5{Å}$$ = 620\;nm$
(b) $\lambda = \frac{{12375}}{{{W_0}}} = \frac{{12375}}{2} = 6187.5{Å}$$ = 620\;nm$
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