1 Common rashes include eczema, poison ivy, hives, and athlete's foot. 2  Infections that cause rashes may be fungal, bacterial, parasitic, or viral.  Over-the-counter products may be helpful treatments for many skin rashes.
The conditions under which this process occurs happen in two ways. According to the Cornell Center for... Atoms emit a photon when an electron falls from a high-energy state to a low-energy state. The conditions under which this process occurs happen in two ways. According to the Cornell Center for...
The lifetime of a system in an excited state is usually short: spontaneous or induced emission of a quantum of energy (such as a photon or a phonon) usually occurs shortly after the system is promoted to the excited state, returning the system to a state with lower energy (a less excited state or the ground state).