1. A step-up transformer is designed to operate from a 12 V supply and to deliver energy at 240 V. If the secondary coil is connected to a 60 W, 240 V bulb, determine (a) the turns ratio of the transformer; (b) the primary current. (4 marks, A) The transformer used to operate a model electric train has 1125 turns on its primary coil and 75 turns on its secondary coil. If it is plugged into a 120 V circuit, what potential difference does the model train receive? (3 marks, A) 3. Draw the magnetic field of a solenoid connected to a battery. (1/1 marks, K/C) 4. Determine the direction of the force on the wire (see the figure). (2 marks, K) m RE a current in a wire 5. A straight conductor is moving up through a magnetic field (see the diagram). Determine the direction of the induced current in the wire. (2 marks, T) &m \\ aconductor 6. Determine the direction of the current induced in the coil by a moving magnet. (2 marks, A) m_a 7. Explain why two parallel wires with opposite currents repel each other. Draw a diagram. [2/2 marks, K/C) _ 8. Show the direction of the current in the depicted wire. (2 marks, T)