Name the three types of spectra and explain briefly the causes of the spectra
1. Continuous spectrum: A continuous spectrum is a spectrum that shows a continuous range of colors without any gaps or lines. This type of spectrum is emitted by hot, dense objects like stars or incandescent light bulbs. The continuous spectrum is caused by the thermal motion of particles in the object, which produces a broad range of wavelengths of light.
2. Emission spectrum: An emission spectrum is a spectrum consisting of bright lines or bands of color against a dark background. This type of spectrum is produced when electrons in an atom or molecule move from a higher energy level to a lower energy level, emitting photons of specific wavelengths in the process. Each element has a unique emission spectrum, making it a useful tool for identifying the composition of stars and other objects in space.
3. Absorption spectrum: An absorption spectrum is a spectrum consisting of dark lines or bands against a bright background. This type of spectrum is produced when light passing through a cool, low-density gas or plasma is absorbed by atoms or molecules, causing them to move to a higher energy level. The absorbed photons correspond to specific wavelengths, resulting in dark lines in the spectrum. Absorption spectra are used to study the composition and temperature of stars, as well as the presence of different elements in the atmosphere of planets and other celestial bodies.