Electromagnetic radiation, generally known as light, is energy composed of electric and magnetic field components. It also displays wavelike properties such as refraction, reflection, diffraction, and interference. Electromagnetic waves can be found in different forms, these include radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, x-rays, and gamma rays. “Despite the fact that all these electromagnetic waves travel at the same speed, they differ in their wavelength and frequency” (Merriam Webster). However, electromagnetic radiation also exhibits particle properties. German physicist Max Plank proposed that energy in electromagnetic radiation can be emitted or absorbed in small units called quanta. Nevertheless, German-American physicist Albert Einstein use Plank’s quantum equations, E= hv, to describe the photoelectric effect. Due to his explanation, light was consider as pockets of energy called photon.
The overall idea of the photoelectric effect defines the phenomenon of the emission line spectrum. In the Bohr model of the hydrogen atom, electrons orbit the nucleus in circular trajectory. These orbits of differing energy are called energy levels. The energy level an electron normally occupies or the lowest energy level is the ground state, located in the inner part of the atom. The electron can move to higher energy level by absorption. This is called the electron’s excited state, when they are further away from the nucleus. The electron can still return to its ground state by putting in action emission, releasing the energy it has absorbed. “Electrons may obtain the energy that excites them by absorbing a photon, which contains small units of quanta” (Bookrags).
Spectroscopy is the use of light, sound, or particle emission to study matter. “Emissions are able to provide information about the properties of the matter under investigation. The device frequently use for this is a spectrometer” (About.com physics). Scientists use spectroscopy to find the chemical composition of stars. They study the intensity and position of emission and absorption lines, meaning they analyze the spectrum light or the light a faraway star gives off in order to get information about that particular star. When they study the spectrum of a star, they see the wavelengths of