A long vertical wire carrying a current of 10A in the upward direction is placed in a region where a horizontal magnetic field of magnitude(`2.0 xx 10^-3)` T exists from south to north. Find the point where the resultant magnetic field is zero.

Explanation

Given `B = 2.0 xx10^(-3) T` (from south to north) A magnetic field will be north to south when required point will place west tot wire. Then form question,`rArr 2.0 xx 10^(-3)` = (2xx10^(-7)xx10)/(r )` .
`rArr = 10^(-3)m =1mm`