1. Figure 1 shows 2 charges at points A and B in the diagram -21 H 6.0 cm +21 p C B 12 cm a) Show that the magnitude of the electric fields t C due to the charge at A is E, = 5.3 x 10' N C-1 b) Using proportionality, show that the magnitude of the electric field at C due to the charge at B is Ez = 1.3 x 10' N C-1 c) Draw the vectors E, and Ez at position C on the diagram above d) Calculate the magnitude of the resultant electric field at C due to the two charges 2. The diagram shown the ionisation of air near the sharp points of a power line a) Give the term describing the phenomenon shown in the diagram b) On the diagrams below, sketch the electric field of a negatively charged conductor with a sharp point c) Explain how the electric field near sharp points may ionise the air d) Electrons move away from the sharp points of the conductor. The energy required to ionise an air molecule is 35 ev. Calculate the maximum number of such particles an electron could ionise while moving a total distance of 10.0 mm from the conductor where the electric field is 7.5 x 10* N C -1