To characterize the amount of damping in a system a ratio called the damping ratio ( also known as damping factor and % critical damping ) is used.
12.
Extremely fast systems, with inductance below critical damping ( 0.8 microhenries ), usually require a shunt diode across the capacitor, to prevent current reversal ( ringing ) from destroying the lamp.
13.
A good simplification is to use the infinite frequency added mass, A _ \ infty = \ lim _ { \ omega \ to \ infty } A ( \ omega ) in the above expression to find a frequency independent critical damping value.
14.
It is common to add a linearised viscous damping term, B _ v to account for the strong non-linearity of the damping force, especially in the critical damping, B _ v = \ xi \ B _ \ text { crit }.
15.
For a damped harmonic oscillator with mass " m ", damping coefficient " c ", and spring constant " k ", it can be defined as the ratio of the damping coefficient in the system's differential equation to the critical damping coefficient:
