A charge q is placed at the centre of the line joining tow equal charges Q. For what value of q will the system of the three charges be in equalilibrium ?

A charge q is placed at the centre of a cube. What is the electric flux passing through the cube?

Four charges each of -Q , are placed at the four corners of a square. Find out the value of a charge q placed at the centre of the square, such that all the charges would be at equilibrium.

Four equal charges q are placed at the four corners of a square of length of each side a. What charge should be kept at the middle of the square so that the system is in equilibrium ?

A charge q is placed at the centre of a cube. What is the electric flux passing through two opposite faces of the cube ?

A charge q is placed at the centre of a cube of side l. What is the electric flux passing through each face of the cube?

Two negative charges each of 1 unit and a positive charge q are placed on a straight line. Where should the charge q be placed and what should be its value for equilibrium of the charges? Is this equilibrium stable, unstable or neutral ?

A charge Q is placed at each of the two opposite corners of a square, A charge q is placed at each of the two other opposite corners of the square. If the resultant electric force field on Q is zero, then how Q and q are related ?

A point charge +q is placed at the centre of a cube of side L. The electric flux emerging from the cube is

A point-charge q is placed at the origin. How does the electric field due to the charge vary with distance r from the origin?

Three charges, each of value q, are placed at the vartices of an equilateral triangle. A fourth charge Q is placed at the centre of the triangle. (i) If Q=-q , will the charge at the vertices move towards the centre of fly away from it? (ii) For what value of Q will the charges remain stationary?