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A cable is composed of two thin isolated parallel wires very close to each other and on the Z axis. One wire carries a current 1, = 34 mA and the other 12 = -7 mA. i) Use Ampere's law to calculate the magnetic field at the point (25, 0, 0) cm. Explain your reasoning and show your workings clearly. (8 marks) ii) If we placed a movable magnetised compass needle at x = 25 cm (north pole towards +Z), what would happen? (4 marks) iii) If we now replace the needle with a square metal loop (2 cm per side) with corners at the coordinates (25,1,1). (25,1,-1). (25,-1,-1) and (25,-1,1) cm, such as Figure 1. Calculate the magnetic dipole moment of the loop when a current of 3 mA flows in the direction from (25,1,-1) to (25,1,1). (6 marks) iv) Calculate the torque on the loop generated by the wires. (7 marks) x 25 Figure 1.