Damping is caused by the resistance in the circuit. It determines whether or not the circuit will resonate naturally (that is, without a driving source). Circuits that will resonate in this way are described as underdamped and those that will not are overdamped. Damping attenuation (symbol ) is measured in nepers per second. However, the unitless damping factor (symbol , zeta) is often a more useful measure, which is related to by
