Two short bar moment each `200 A-m^(2)` are placed as shown in the figure at the corners of a square of side 10 cm.The magnetic induction at P is

Options

A. `8xx10^(-2) T`
B. `6xx10^(2)T`
C. `2xx10^(-2)T`
D. `6xx10^(-1)T`

Answer

B

Explanation

due to I magnet `B_(1)` at P=`(mu_(0))/(4pi)(2M)/(r^(3))`
`B_(1)=10^(-7)xx2xx(200)/(10^(-3))=4xx10^(-2)T`

Due to II magnet `B_(2)` at P,
`B_(2)=(mu_(0))/(4pi)=10^(-7)xx(200)/(10^(-3))=2xx10^(-2) T`Both act along same ling, `B=B_(1)+B_(2)=6xx10^(-2)T`.