What does a spectrometer measure?

A spectrometer is an instrument specifically designed to disperse light into its component wavelengths or frequencies, thereby allowing the measurement of the intensity of light as a function of wavelength. This capability is fundamental to many applications, including analyzing the spectral composition of light sources, identifying materials based on their absorption or emission spectra, and conducting research in fields such as chemistry and physics.

By plotting the intensity of light against its corresponding wavelengths, a spectrometer provides a comprehensive view of the behavior of light across a spectrum, facilitating a deeper understanding of the properties and interactions of different materials with light. This ability to measure intensity as a function of wavelength is what distinguishes spectrometry from other methods of light measurement, such as measuring the speed of light or temperature of a source. Thus, the correct choice accurately reflects the primary function of a spectrometer.