Q4. An electric field ( (2 imes 1010 mathrm{~V} / mathrm{m}) ) is applied to a piezoelectric material. The polarization of the material is a function of strain ( ( arepsilon ) ) and varies as per the below Equation 4.1 [ P=rac{1}{arepsilon} imes log _{e} arepsilon ] The term ( e(=2.71) ) is a mathematical constant. Find out [ ext { Page } 15 ] (a) the maximum possible electric displacement if ( arepsilon_{0}=8.854 imes 10^{-12} mathrm{Fm}^{-1} ). [5 Marks] (b) the maximum electrostatio energy density [2 Marks] (c) the stress in the material at ( 5 % ) strain. [3 Marks]

Q4. An electric field (21010V/m) is applied to a piezoolectric material. The polarization of the material is a function of strain ( E ) and varies as per the below Equation 4.1 P=e1log6 The terme (=2.71) is a mathematical constant. Find out Page15 (a) the maximum possible electric displaceinent if c5=8.8541012Fm1. [5 Marks] (b) the maximum electrostatio eicrey density [2 Marks] (c) the stress in tho matcrial at 5% strain: [3 Marks]