An electric dipole is formed by placing charges ` pm 20 xx 10 ^( -6 ) C ` at a distance 2 mm. Calculate the electric field at a point on the perpendicular bisector of the axis of the dipole situated at a distance 10 cm from the midpoint of the dipole.

Explanation

Electric field, ` E = ( 1 ) /( 4pi in _ 0 ) * (p ) /( ( r ^ 2 + l^ 2 ) ^ ( 3//2 ) ) `
[ here, ` l = 1 xx 10 ^( -3 ) m, p = q xx 2 l `
` = 2 0 xx 10 ^( - 6 ) xx 2 xx 10 ^( - 3 ) = 40 xx 10 ^( - 9 ) cm]`
` therefore E = ( 9xx 10^( 9) xx 40 xx 10 ^( -9) ) /( [ (10 xx 10 ) ^( -2 ) + (1 xx 10^( -3 ) ) ^ 2 ]^( 3//2) ) = ( 360)/((10^( -2) + 10^( -6))^(3//2))`
` = 36 xx 10 ^( 4 ) N *C^( - 1 ) `