- The ‘input’ (x) or physical quantity being measured, changes over time (t) and is therefore said to be ‘unsteady’
- The output (y), as a function of time y(t) and can generally be given as a factor (K) of the input as a function of time
- Mathematically, if we let f(t) be the input to the system as a function of time and y(t) be the output, then the relationship between them is
y(t) = Kx(t)
- Dynamic characteristics describe the behaviour of a measurement system between the time a measured quantity changes value and the system obtains a steady output in response