Question

A device for accurately generating small forces between two wires can be created by the rectangular circuits shown in the figure on the worksheet for this problem. In the left circuit, the battery has an emf of ε1 = 6 V and a resistor with fixed resistance R1 = 4 ohms. In the right circuit, the battery has emf of ε2 = 7 V and a variable resistor with resistance R2 ohms. The circuits are L = 12 cm wide and D = 2 mm apart. (a) To what resistance R2 in ohms should the variable resistor be set to create a force of magnitude 2.0 x 10−5 N between the wires? (Enter the answer as a decimal number to three significant figures without units in answer box for this problem.) (b) Will the force be attractive or repulsive? Justify your answer by drawing the direction of the magnetic field in the vicinity of each wire on the circuit diagram and describing how the force is produced on each wire in those fields

Answer 1