Two long, straight, parallel wires are 1.00m apart (as shown in Fig). The upper wire carries a current `I_1` of 6.00A into the plane of the paper.

What is the magnitude of the net field at S?

Options

A. `4.1xx10^-6T`
B. `1.6xx10^-6T`
C. `3.2xx10^-6T`
D. `2.1xx10^-6T`

Answer

D

Explanation

(d) The magnitude of the field at S is given by the sum of the squres
of the two fields because they are at right angles. So,
`B_S=sqrt(B_1^2+B_2^2)=(mu_0)/(2pi)sqrt(((I_1)/(r_1))^2+((I_2)/(r_2))^2)`
`=(mu_0)/(2pi)sqrt(((6.00A)/(0.500m)-(2.00A)/(1.50m)))`
`=2.1xx10^-6T`