If the work function of a photometal is 6.825 ;eV. Its threshold … - Vidyadip

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) ${\lambda _0} = \frac{{12375}}{{6.825}} = 1813\,{Å} \approx 1800{Å}$

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