Final answer:
The statement that bandwidth is a range within a band of frequencies or wavelengths is true. Bandwidth is tied to the energy range within an energy band and can be applied to the electromagnetic spectrum, where different parts are measured in specific units due to inverse proportionality of wavelength and frequency.
Step-by-step explanation:
The statement that bandwidth is a range within a band of frequencies or wavelengths is true. Bandwidth refers to the difference in energy between the highest and lowest energy levels in an energy band, which corresponds with the range of frequencies or wavelengths that the band covers. In the context of the electromagnetic spectrum, this can be seen with the visible light portion, where different colors are associated with specific wavelengths and frequencies. Wavelength and frequency are inversely proportional; as wavelength increases, frequency decreases, which is why different technologies are used to measure different parts of the electromagnetic spectrum.
For example, the visible spectrum represents a narrow band of wavelengths between about 400 and 700 nanometers and is typically discussed using units of nm or angstroms. On the other hand, radio waves are often described in terms of frequency, with units like megahertz (MHz). This reflects the historical and practical reasons for using different units for different parts of the electromagnetic spectrum.