In the paper, some aspects of nonlinearity of micro/nanoelectromechanical systems (MEMS/
NEMS) are presented. Because of great values of strains of micro/nanobeams the nonlinear
description is necessary. Particularly, the nonlinear inertia term is added to equation relating
to motion of the beam. Numerical calculations of resonance curves and instability regions
are given. Results are presented on graphs.
