Question

Three points caharges are placed at the comers of and equilateral triangel of side `L` as shown in the figure .
` .
A. The potential at the centroid of the triangle is zero .
B. The electric field at the centroid of the triangle is zero.
C. The dipole moment fo the system is ` sqrt2 qL`
D. The dipole moment fo the system si ` sqrt3 qL`.

Answer 1

Correct Answer - A::D
(A) `V=V_A +_B + V_c`
`= (Kq)/x + (Kq)/x + (K(-2q))/x xx ` graph

` V=0`
(B) ` vec E_0 = vec E_A + vec E-B + vec E_C != 0`
(C) `vec _("net") = vec P_1 + vec P_2`
since `P_1 =P_1 =qL`

so `P_("net") = 2P _1 cos (theta)/2 = 2 qL cos 30^@`
` P_("net") = sqrt 3qL`.