Along with time-invariance, impulse responses completely characterize dynamic systems with this property.
For a sinusoidal input voltage with a given frequency, this type of circuit will also output a sinusoidal voltage of the given frequency. For some transport phenomena, responses with this property may be modeled using the Kubo formula. In the context of engineering, the principle of superposition only holds for systems with this property. Along with time-invariance, impulse responses completely characterize dynamic systems with this property. The Dirac delta function of the difference between r and r' ["r prime"] is equal to a differential operator with this property applied to a Green's function. This property cannot be possessed by a set of differential equations that exhibit chaotic behavior. For 10 points, identify this property of equations that do not have quadratic or higher-order terms in them, which shares its name with an adjective that describes motion constrained to one dimension.
For a sinusoidal input voltage with a given frequency, this type of circuit will also output a sinusoidal voltage of the given frequency.
linear [prompt on "causal" before mention]