6. A magician wants to build a device that will allow him to levitate for his magic act. His device has a wire 10 m long bent into a loop. If the magician's mass is 75 kg, and Earth's magnetic eld (perpendicular to the wire) is 4.8 X 10~1 T, how much current must move through the wire for the magician to levitate? 7. Aprinter is connected to a 1.0 to cable. If the magnetic force is 9.1 X 1&5 N, and the magnetic eld is 1.3 X 104 T, how much current passes through the wire? 8. Suppose a highvoltage cable carries 1.5 x 103 A of current 15 km along a straight city road. The Earth's magnetic eld at this latitude is at a 45angle to the power line and has a magnitude of 2.3 X 105 T. What is the magnetic force exerted on the cable? 9. A fax machine requires 1.4 A 9_f current to pass through a 2 m cable in order to work. If the magnetic eld perpendicular to the cable is 3.6 X 104 T, what is the magnetic force exerted on the cable? 10. Light bulb laments can weaken partially because of the magnetic forces acting on them. If a lament weakens enough, it breaks, and the light bulb \"burns out.\" Suppose a current of 0.5 Amoves through a 5 cmlong wire lament and that a magnetic eld of 1.3 X 104 T acts on the wire. What is the magnetic force acting on the lament? (Assume that the lament is a straight wire.)