PART A: PROBLEMS (40 MARKS ) Answer questions 1 and 2 in the space provided. Answer the remaining questions on a separate sheet of paper. You may use the back of this sheet if you wish. (5) 1. A positive charge of +3.2 x 10 * C experiences an (9) 2. Calculate the electric field intensity midway between electric force of magnitude 4.0 N, acting to the left. two negative charges of 4.3 x 10" C and 8.6 x 10-" What is the magnitude and direction of the electric C that are 20 cm apart. Include a diagram of the field at that point? situation. (15)3. Two 2.0 g spheres are attached to each end of a silk thread 1.20 m long. The spheres are given identical charges and the midpoint of the thread is then suspended from a point on the ceiling. The spheres come to rest in equilibrium, with their centres 15 cm apart. (a) Draw a diagram of the situation. (b) Draw a FBD of one of the spheres. (c) what is the magnitude of the charge on each sphere? (11)4. Two small oppositely charged spheres X and Y are fixed in position, as shown, 15 cm and have charges of +40 UC and -40 UC, respectively. Determine the 60" magnitude and direction of the net electrical field ($ ) at point Z in the diagram given, due to the charges at points X and Y. (Hint: Z is a small positive test charge!) 30