(a) The charges each `Q` are placed at `x - d , 2d , 4d ,…oo`. Find electric potential at origin `O`.
(b) A charge `+Q` is placed at each of the points `x = d , x = 3d ,x = 5d ,…..,oo` on the `x`-axis , and a charge `-Q` is placed at each of the points `x = 2d , x = 4d , x= 6d , ...,oo`.Find the electric potential at the origin `O`.

An infinite number of charges each numerically equal to q and of the same sign are placed along the x-axis at x = 1, x = 2, x = 4, x = 8 and so on. Find electric potential at x=0 .

Equal charges q are placed at the three corners B, C, D of a square ABCD of side 'a'. The ratio of potential at A to centre O is

A charge +q is fixed at each of the points x=x_0 , x=3x_0 , x=5x_0 ,………… x=oo on the x axis, and a charge -q is fixed at each of the points x=2x_0 , x=4x_0 , x=6x_0 , ………… x=oo . Here x_0 is a positive constant. Take the electric potential at a point due to a charge Q at a distance r from it to be Q//(4piepsilon_0r) .Then, the potential at the origin due to the above system of

A charge q is placed at point D of the cube. Find the electric flux passing through the EFGH and face AEHD .

3 charges are placed in a circle of radius d as shown in figure. Find the electric field along x-axis at centre of circle.

A point charge q is placed at a distance d form the center of circular disc of radius R . Find electric flux through the disc due to that charge

A point charge q_1 = + 2muC is placed at the origin of coordinates. A second charge, q_2 = - 3muC , is placed on the x-axis at x = 100cm . At what point (or points) on the x-axis will the absolute potential be zero?

Two large identical plates are placed in front of each other at x =d and x = 2d as shown in the figure. If charges on plates are Q and -5Q , the potential versus distance graph for the region x = 0 = 3d is : (d is very small and potential at x = 0 is V_(0) )