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Calculate the frequency of electromagnetic radiation whose wave number is 10⁴ cm⁻¹.
- 3 * 10¹⁴ Hz
- 3 * 10¹⁰ Hz
- 3 * 10⁴ Hz
- 3 * 10¹⁸ Hz
Correct answer: 3 * 10¹⁴ Hz
Solution
Frequency nu = c * nu_bar = (3 * 10⁸ m/s) * (10⁶ m⁻¹) = 3 * 10¹⁴ Hz. The wave number 10⁴ cm⁻¹ falls in the infrared region.
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