An infinite number of charges, each of charge $1~\mu\text C,$ are placed on the $x\text-$axis with co-ordinates $x=1,2,4,8,....\infty .$ If a charge of $1~\text C$ is kept at the origin, then what is the net force acting on $1~\text{C}$ charge?

1.	$9000~\text N$	2.	$12000~\text N$
3.	$24000~\text N$	4.	$36000~\text N$

A charge q is placed at the centre of the line joining two equal charges Q. The system of the three charges will be in equilibrium, if q is equal to 

(1) $-\frac{Q}{2}$

(2) $-\frac{Q}{4}$

(3) $+\frac{Q}{4}$

(4) $+\frac{Q}{2}$ 

The figure shows the electric lines of force emerging from a charged body. If the electric fields at A and B are E_A and E_B respectively and if the distance between A and B is r, then:

1. $E_{A}~>~E _{B}$
2. $E_{A}~<~E _{B}$
3. $E_{A}~=~\frac{E_{B}}{r^{}}$
4. $E_{A}~=~\frac{E_{B}}{r^{2}}$

$ABC$ is an equilateral triangle. Charges $+q$  are placed at each corner. The electric intensity at $O$ will be: 

The magnitude of electric field intensity E is such that, an electron placed in it would experience an electrical force equal to its weight is given by 

(1) mge

(2) $\frac{mg}{e}$

(3) $\frac{e}{mg}$

(4) $\frac{e^2}{m^2}g$

An uncharged sphere of metal is placed in between two charged plates as shown. The lines of force look like 

(1) A

(2) B

(3) C

(4) D

The magnitude of electric field E in the annular region of a charged cylindrical capacitor 

(1) Is same throughout

(2) Is higher near the outer cylinder than near the inner cylinder

(3) Varies as 1/r, where r is the distance from the axis

(4) Varies as 1/r², where r is the distance from the axis

A metallic solid sphere is placed in a uniform electric field. The lines of force follow the path(s) shown in figure as 

(1) 1

(2) 2

(3) 3

(4) 4