(a) GaAs is a piezoelectric material with piezoelectric constant e = 1.6 × 10⁻⁵ C/cm2. What pressure is generated on the crystal by a potential drop of 5 V applied across a slab of GaAs with thickness 1 mm?

(b) The relevant compliance constant of GaAs is S = 1.7×10⁻¹² cm²/dyne. How much does the surface of a 1 mm GaAs crystal actually move under the electric field calculated in part (a)?