In: Physics
Three long wires are all parallel to each other and are all in the xy plane. Wire 1 runs along the y axis and carries a current of 1.64 A in the +y direction. Wire 2 runs along the
x = 25.0 cm
line and carries a current of 4.04 A in the −y direction.
(a) Determine the location of wire 3 on the x axis so that when it carries a certain current (to be determined later) each wire experiences no net force.
(b) Determine the magnitude and direction of the current in wire 3.
magnitude ?
direction?
Suppose the wire is to the left of origin at a distance d on x-axis and parallel to the y-axis , then it must balance the attractive force between wire 1 and 2. Balancing the forces on wire 1
..................(1)
Balancing forces on wire 2
.................(2)
Dividing equation 1 and 2 we get
2.46d = d + 25
1.46d = 25
d = 17.12 cm
The wire must be at x = -17.12 cm
b) Putting value of d in (1)
I3 = 0.1616 d =0.1616(17.13)
I3 = 2.77 A
the current must be along negative y-axis. This is because if two wires have the same current direction they attract each other and if they have opposite current direction they repel each other.