MCQ
If work function of metal is $3\ \mathrm{eV}$ then threshold wavelength will be
- ✓$4125 \mathring A$
- B$4000 \mathring A$
- C$4500 \mathring A$
- D$5000 \mathring A$
✓
Answer
Correct option: A.
$4125 \mathring A$
$\lambda_0=\frac{12375}{W_0(\mathrm{eV})}=\frac{12375}{3}=4125 \mathring A$
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