Three parallel long straight conductors are carrying equal currents i each as shown. Th e conductors are passing tlrrough the vertices of equilateral triangle of side 'a'.

Find the magnetic firld at C the centroid of triangle

Explanation

`B_(1)=B_(2)=B_(3)=(mu_(0))/(2pi)(i)/((a//sqrt3))`
`abs(vecB_(1)+vecB_(2)+vecB_(3))=2B_(1)`
`becausevecB_(1)` and `vecB_(2)` are acting at 120° to each other and `vecB_(3)` is along angular bisector of the above
`rArrB_("net")=(mu_(0)sqrt3i)/(pia)`