7- The electric potential along the x-axis is V = 50 e ** volt, where x is in meters. What is E(x) at: x = 1.2 m and (b) x = 2.0 m? 8- 4000.0 pJ (1 Pico = 10!\" ) energy is stored in a cylindrical region with diameter of 20.0 cm and length of 28.0 cm region of uniform electric field. What is electric field strength? 9- A8.0-cm-diameter parallel-plate capacitor has 4.0 mm spacing. The electric field strength inside the capacitor is 1.0 * 105 V/m. a. What is the potential differences across the capacitor? b. How much charge is on each plate? c. What is area charge density? d. What is the Stored energy in capacitor? e. What is Energy density of capacitor? f. What is Energy of capacitor if we put paper with dielectric of 4.7 between plates in above conditions? 10- What is capacitance of a cylindrical capacitor with the length of 14.0 cm and inner diameter of 8.0 cm and outer diameter of 12.0 cm with dielectric material of Mica with dielectric constant of 7.5 between two cylinders? 11-Derive equation for potential differences of a quarter circle charged rod with the radius of R at the center. (b) Use the result of part (a) and find potential differences of the semicircle charged rod with charge of 80.0uC and radius of 20.0cm. 12-Two non-identical spherical drops of mercury one with charge of 30.0 nC anda potential of 500.0 V and the other one with charge of 40.0 nC and potential of 700.0 Vat the surface. The two drops merge to form a single drop. What is the potential at the surface of the new drop