MCQ
If the work function of a photometal is $6.825 \;eV$. Its threshold wavelength will be ............. $\mathring A$ $(c = 3 \times {10^8}\,m/s)$
- A$1200 $
- ✓$1800 $
- C$2400$
- D$3600 $
✓
Answer
Correct option: B.
$1800 $
b
(b) ${\lambda _0} = \frac{{12375}}{{6.825}} = 1813\,{Å} \approx 1800{Å}$
(b) ${\lambda _0} = \frac{{12375}}{{6.825}} = 1813\,{Å} \approx 1800{Å}$
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