MCQ
The frequency of light ray having the wavelength $3000 Å$ is
- A$9 × {10^{13}}\, cycles/sec$
- ✓${10^{15}} \,cycles/sec$
- C$90\, cycles/sec$
- D$3000\, cycles/sec$
✓
Answer
Correct option: B.
${10^{15}} \,cycles/sec$
b
(b)$\nu = \frac{c}{\lambda } = \frac{{3 \times {{10}^8}}}{{3000 \times {{10}^{ - 10}}}} = {10^{15}}$cycles/sec
(b)$\nu = \frac{c}{\lambda } = \frac{{3 \times {{10}^8}}}{{3000 \times {{10}^{ - 10}}}} = {10^{15}}$cycles/sec
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