Final answer:
False. The wavenumber is inversely proportional to the wavelength of an electromagnetic wave.
Step-by-step explanation:
False. The wavenumber is not directly proportional to the wavelength of an electromagnetic wave. The wavenumber is actually inversely proportional to the wavelength.
Wavenumber (k) is defined as the number of waves per unit distance and is measured in reciprocal meters (m-1) or inverse centimeters (cm-1). It represents the spatial frequency of the wave. The formula for wavenumber is given by k = 2π/λ, where λ is the wavelength. As the wavelength increases, the value of wavenumber decreases, and vice versa.