MCQ
If threshold wavelength for sodium is $6800 \mathring A$ then the work function will be
- ✓$1.8 \mathrm{eV}$
- B$2.5 \mathrm{eV}$
- C$2.1 \mathrm{eV}$
- D$1.4 \mathrm{eV}$
✓
Answer
Correct option: A.
$1.8 \mathrm{eV}$
$W_0=\frac{12375}{6800}=1.8 \mathrm{eV}$
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