7. The Trans Siberian railroad runs east-west near the arctic circle where the earth's magnetic field is nearly vertical with a magnitude of 0.57 mT. The track that the wheels run on measures 2.3 meters between rails. A train is travelling west at a speed of 55 mls. As the wheel axle moves through the earth's magnetic eld an EMF in generated that causes a current to ow through the rails. The wheels of a second train standing still, far enough ahead to not interfere with this train, completes the circuit with a 4.5 Q resistance. a) (5 points) What is voltage difference across the width of the axle and which side left or right will be at the higher potential as seen facing toward the front of the train? b) (5 points) What is the resulting magnitude and direction of the force of magnetism acting on this axle