A current of 10A is established in a long wire along the positive z-axis. Find the magnetic field `(vec B) ` at the point (1m , 0 , 0).

Explanation

Wthe the magnetic field is swiched the tension increase . The lenth of wire .
` Y = (T/A) //(Deltal/L)`
` or AL = (TI)/(TA)= (iaB) //(Ypi r^(2)`
`2 pi xx Delta r = (iaB 2pi a )//(Y pi r^2 ) ` .