The magnetic field at centre , P will be

Options

A. `(mu_(0))/(4pi)`
B. `(mu_(0))/(pi)`
C. `(mu_(0))/(2pi)`
D. `4mu_(0)pi`

Answer

C

Explanation

Magnetic field at point P will be, `B= (mu_(0))/(4pi) (2i_(2))/((r//2)) -(mu_(0))/(4pi) (2i_(1))/((r//2))= (mu_(0))/(4pi) (4)/( r) (i_(2)- i_(1))`
`=(mu_(0))/(4pi ) (4)/(5) (2.5- 5.0) = -(mu_(0))/(2pi)` (into plane of paper) -ve sign show that B is acting inwards i.e., into the plane.