Finding the magnetic field at a point with two wires.

[cndman]

Homework Statement

Two parallel wires, each carrying a current of 2.2 A in the same direction, are shown in the figure . Find the magnitude of the net magnetic field at points A, B, and C.

Homework Equations

B=(μ*I)/(2*pi*r)

μ=4*pi*10^-7

The Attempt at a Solution

I believed I could simply calculate the magnetic field from each of the two wires then add up them up so

B=(μ*2.2)/(2*pi*.075)= .000059

B=(μ*2.2)/(2*pi*.225)= .000002

Answer is in μT so I've tried 61, .000061, 57, ect.

I know B is 0.

 

[gneill]

Homework Statement

Two parallel wires, each carrying a current of 2.2 A in the same direction, are shown in the figure . Find the magnitude of the net magnetic field at points A, B, and C.

Homework Equations

B=(μ*I)/(2*pi*r)

μ=4*pi*10^-7

The Attempt at a Solution

I believed I could simply calculate the magnetic field from each of the two wires then add up them up so

B=(μ*2.2)/(2*pi*.075)= .000059

B=(μ*2.2)/(2*pi*.225)= .000002

Answer is in μT so I've tried 61, .000061, 57, ect.

I know B is 0.

Magnetic fields are vector fields. That means they have directions as well as magnitudes. You need to take the field directions into account when you add them at a given point (vector addition). Do you recall learning about the right-hand rule for currents and magnetic fields?

You might also consider using scientific notation for your values to avoid all those leading zeros and to manage appropriate significant figures in the values.