An element `Deltavecl=Deltaxhati` is placed at the origin as shown in figure and carries a current `I=2A`. Find out the magnetic field at a point P on the y-axis at a distance of `1*0m` due to the element `Deltax=1cm`. Give also the direction of the field produced.

Answer

`2xx10^-9T` in +z-direciton

Explanation

Here, `Idvecl=IDeltaxhati`, where `I=2A`,
`Deltax=1cm=10^-2m`, `r=1*0m` and `vecr=1*0hatj`
`dvecB=(mu_0)/(4pi)(Idveclxxvecr)/(r^3)=(mu_0)/(4pi)(IDeltaxhatixx(1*0hatj))/(r^3)`
`=(mu_0)/(4pi)((IDeltaxxx1*0))/(r^3)(hatixxhatj)=(mu_0)/(4pi)(IDeltaxxx1*0)/(r^3)xxhatk`
`=10^-7xx(2xx10^-2xx1*0)/(1^3)hatk`
`=2xx10^-9T` in +z direction.