1. What is Wavenumber?

Wavenumber is the spatial frequency of a wave, measured in cycles per unit distance (typically per meter). It represents the number of wave cycles that exist over a specified distance.

2. How Does the Calculator Work?

The calculator uses the wavenumber equation:

Where:

• Frequency — Wave frequency in Hertz (Hz)
• c — Speed of light (typically 3×10⁸ m/s in vacuum)

Explanation: The equation converts temporal frequency (cycles per second) to spatial frequency (cycles per meter).

3. Importance of Wavenumber

Details: Wavenumber is particularly important in spectroscopy, where it's used to characterize electromagnetic radiation. It's directly proportional to energy and frequency.

4. Using the Calculator

Tips: Enter frequency in Hz and speed of light in m/s (default is 3×10⁸ m/s for vacuum). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between wavenumber and wavelength?
A: Wavenumber is the reciprocal of wavelength, representing spatial frequency rather than the physical length of one wave cycle.

Q2: What are typical wavenumber units?
A: The SI unit is m⁻¹ (reciprocal meters), but cm⁻¹ is commonly used in spectroscopy.

Q3: Does wavenumber change with medium?
A: Yes, since the speed of light changes in different media, the wavenumber for a given frequency will also change.

Q4: How is wavenumber related to energy?
A: In spectroscopy, wavenumber is directly proportional to energy (E = hcν̃, where ν̃ is wavenumber).

Q5: Why use wavenumber instead of frequency?
A: In spectroscopy, wavenumber is often more convenient as it's directly proportional to energy and provides better scale for molecular transitions.