14. What are the magnitude and direction of the electric field strength at point Z in Figure 2? 91 = -2.0 x 10-5 C 92 = 8.0 x 10-6 C + 60.0 cm 30.0 cm X Y Z Figure 2 18. A charge of 1.2 X 10-3 C is fixed at each corner of a rectangle 30.0 cm wide and 40.0 cm long. What are the magnitude and direction of the electric force on each charge? What are the electric field and the elec- tric potential at the centre? 20. A 1.0 X 10-6 C test charge is 40.0 cm from a 3.2 X 10-3 C charged sphere. How much work was required to move it there from a point 1.0 X 102 cm away from the sphere