descriptor of a linear system in the frequency domain that relates the output motion spectrum (displacement, velocity or acceleration) to the input force spectrum
NOTE 1 The frequency response function is generally defined as:
NOTE 2 H(w) is a complex function containing magnitude and phase information.
NOTE 3 Common definitions of standard and inverse FRF are:
a. accelerance or inertance (see 3.2.1)
b. apparent or dynamic mass (see 3.2.2)
c. dynamic compliance or flexibility (see 3.2.11)
d. dynamic stiffness (see 3.2.12).
e. impedance (see 3.2.22)
f. mobility (see 3.2.24).