Question

A long wire carrying a current `i` is bent to form a plane angle. The magnitude of magnetic field at height `d`, above the point of bending
A. `(sqrt(2) mu_(0)i)/(4pid)`
B. `(3sqrt(2) mu_(0)i)/(4pid)`
C. `(5sqrt(2) mu_(0)i)/(4pid)`
D. `(7sqrt(2) mu_(0)i)/(4pid)`

Answer 1

Correct Answer - A

At distance `d` above `O`:
`B_(1)=B_(2)=(mu_(0)i)/(4pid)`
`B_(1)` is `bot^(ar)` to `B_(2)`
Resultant to `B_(1)` and `B_(2)`
`B=sqrt(B_(1)^(2)+B_(2)^(2))=sqrt(2).(mu_(0)i)/(4pid)`