

InterviewSolution
Saved Bookmarks
1. |
A long straight wire in the horizontal plane carries as curret of 75 A in north to south direction, magnitude and direction of field B at a point 3 m east of the wire isA. `4xx10^(-6)T`, vertical upB. `5xx10^(-6)T`, vertical downC. `5xx10^(-6)T`, vertical upD. `4xx10^(-6)T`, vertical down |
Answer» Correct Answer - C From Ampere circuital law `ointvecB.vec(dl)=mu_(0)I_("enc")` `Bxx2piR=mu_(0)I_("enc")` `B=(mu_(0)I_("enc"))/(2piR)=2xx10^(-7)xx(75)/(3)=5xx10^(-6)T` The direction of field at the given point will be vertical up determined by the screw rule or right hand rule. |
|