has 21 nonzero components: f$_{1111}$ = − µ$_{11}$ a$_{11}$ , f$_{2211}$ = f$_{3311}$ = − µ$_{12}$ a$_{11}$ f$_{1221}$ = f$_{2121}$ = f$_{1331}$ = f$_{3131}$ = − µ$_{44}$ a$_{11}$ f$_{2222}$ = − µ$_{11}$ a$_{22}$ , f$_{1122}$ = f$_{3322}$ = − µ$_{12}$ a$_{22}$ f$_{1212}$ = f$_{2112}$ = f$_{2332}$ = f$_{3232}$ = − µ$_{44}$ a$_{22}$ f$_{3333}$ = − µ$_{11}$ a$_{33}$ , f$_{1133}$ = f$_{2233}$ = − µ$_{12}$ a$_{33}$ f$_{1313}$ = f$_{3113}$ = f$_{2323}$ = f$_{3223}$ = − µ$_{44}$ a$_{33}$ u$_{1}$ ( x, y, z, t ) ≡ u ≈ − zw $^{′}$( x, t ) , u$_{2}$ ( x, y, z, t ) ≈ 0 , u$_{3}$ ( x, y, z, t ) ≈ w ( x, t ) , (6) S$_{11}$ ≡ ε$_{x}$ = − zw $^{′′}$, S$_{22}$ ≡ ε$_{y}$ = 0 , S$_{33}$ ≡ ε$_{z}$ = 0 , S$_{12}$ = S$_{21}$ ≡ γ$_{xy}$ = S$_{13}$ = S$_{31}$ ≡ γ$_{xz}$ = S$_{23}$ = S$_{32}$ ≡ γ$_{yz}$ = 0 . (7) − E$_{3}$ ≡ − E$_{z}$ = a$_{33}$P$_{3}$ + d$_{31}$ε$_{x}$ + f$_{1133}$u$_{,xz}$ + f$_{1313}$u$_{,zx}$ + f$_{3113}$w$_{,xx}$ = a$_{33}$P$_{z}$ − ( d$_{31}$z − f$_{1133}$ ) w ′′ In this work, we do not consider the terms with b$_{ijkl}$ , e$_{ijkl}$ , and g$_{ijk}$ coefficients although it might be done without difficulties. Using the equations (3)-(5) we derive the equations of motion for a dielectric nanoswitch. Here we consider a cantilever switch which may be presented as a Euler-Bernoulli or Timoshenko beam or 2-D narrow plate (Fig. 1). The load applied to the free edge of the cantilever simulates the case of nonuniform strain. Within the framework of the Euler-Bernoulli model, the displacement can be written as Hence, based on the equations (6), the strains are equal to We assume that the electric field acts only in z − direction. Then, from (5) we can express E$_{z}$ as III. EULER-BERNOULLI BEAM MODEL 5