Two long, straight wires are separated by 0.12 m. The wires carry currents of 2.
ID: 1373178 • Letter: T
Question
Two long, straight wires are separated by 0.12 m. The wires carry currents of 2.5 A in opposite directions, as the drawing indicates.
(a) Find the magnitude of the net magnetic field at the point A.
(b) Find the magnitude of the net magnetic field at the point B.
Explanation / Answer
A) at point A
Bnet = B1 - B2
= mue*I/2*pi*r1 - mue*I/(2*pi*r2)
= (mue*I/2*pi)*(1/r1 - 1/r2)
= (4*pi*10^-7*1/(2*pi))*(1/0.03 - 1/0.15)
= 5.33*10^-6 T(out of the page)
B) at point B
Bnet = B1 + B2
= mue*I/2*pi*r1 + mue*I/(2*pi*r2)
= (mue*I/2*pi)*(1/r1 + 1/r2)
= (4*pi*10^-7*1/(2*pi))*(1/0.06 + 1/0.06)
= 6.67*10^-6 T (in to the page)