FIGURE 28-3
-Fig. 28-3 shows three long, parallel current-carrying wires. The magnitudes of the currents are equal and their directions are indicated in the figure. Which of the arrows drawn near the wire carrying current 1 correctly indicates the direction of the magnetic force acting on that wire?
A)A
B)B
C)C
D)D
E)The magnetic force is equal to zero.

Question

FIGURE 28-3 
-Fig. 28-3 shows three long, parallel current-carrying wires. The magnitudes of the currents are equal and their directions are indicated in the figure. Which of the arrows drawn near the wire carrying current 1 correctly indicates the direction of the magnetic force acting on that wire?
A)A 
B)B 
C)C 
D)D 
E)The magnetic force is equal to zero.

Quizplus · Accepted Answer

The magnetic force on a current-carrying wire in a magnetic field is given by the right-hand rule. For wire 1, the magnetic fields due to wires 2 and 3 will exert forces. Since the currents in wires 1 and 2 are in opposite directions, wire 1 will experience a force towards wire 3. Similarly, the current in wire 3 is in the same direction as wire 1, so wire 1 will experience a force away from wire 3. The net force will be towards wire 3, which corresponds to arrow A.

FIGURE 28-3 -Fig. 28-3 Shows Three Long, Parallel Current-Carrying Wires. the Magnitudes