pعند : B2=\frac{\mu I2}{2\pi d}

=\frac{4\pi\times10-7\times10}{2\pi\times10\times10-2}=2\times10-5T​​​​​​B1=Bt-B2=\left(6\times10-5\right)-\left(2\times10-5\right)

​​​​​​​=4\times10-5T

​​​​​​​\therefore4\times10-5=\frac{4\pi\times10-7\times I1}{2\pi\times10\times10-2}

​​​​​​​\therefore I1=20A

Qعند ​​​​​​​B1=\frac{4\pi\times10-7\times20}{2\pi\times30\times10-2}

​​​​​​​=1.33\times10-5T

​​​​​​​B2=\frac{4\pi\times10-7\times10}{2\pi\times10\times10-2}=2\times10-5T

​​​​​​​Bt=B2-B1

​​​​​​​=\left(2\times10-5\right)-\left(1.33\times10-5\right)

​​​​​​​=0.67\times10-5T​​​​​​​