Two straight infinitely long and thin parallel wires are spaced 0.1m apart and carry a current of 10A each. Find the magnetic field at a point distance 0.1m from both wires in the two cases when the currents are in the (a) same and (b) opposite directions.

Answer

A, B, C

Explanation

(i)`B_(1)=B_(2)=(mu_(0)i)/(2pid)`
`B_(Net)=sqrt3B_(1)`
`=sqrt3xx(2xx10^(-7)xx10)/0.1`
`=2sqrt3xx10^(-5) tesla`
(ii) `B_(Net)=B_(1)`
`=2xx10^(-5) tesla`