Electric Charge...

The surface charge density on a copper sphere is $$\sigma$$. So the intensity of electric field on its surface will be:

At a certain distance from a point charge the electric field is $$500\ V/m$$ and the potential is $$3000\ V$$. What is this distance:

An electron (of charge $$-e$$) revolves around a long wire with uniform charge density $$\lambda$$ in a circular path of radius $$r$$. Its kinetic energy is given by:

Shown below is a distribution of charges. The flux of electric field due to these charges through the surface S is

The figure shows a family of equipotential surfaces and four paths along which an electron is made to move from one surface to another as shown in figure.
1) What is the direction of electric field?
2) Rank the paths according to the magnitude of the work done, greatest first

Two charges are at a distance $$d$$ apart. If a copper plate of thickness $$d/2$$ is kept between them, then effective force will be

A point charge of value $$10^{-7}\ C$$ is situated at the centre of cube of $$1\ m$$ side. The electric flux through its total surface area is:

Position vectors of two point charges of $$1nC$$ each are $$(1,1,-1)$$m and $$(2,3,1)$$m respectively. Magnitude of electric force acting between them is ___N.

In the figure shown here, A is a conducting sphere and B is a closed spherical surface. If a-q change is placed at C near A, then the electric flux through the closed surface is -

A point charge of $$+6\mu C$$ is placed at a distance 20 cm directly above the centre of a square of side 40 cm. The magnitude of the flux through the square is