Electric Charge...

A cone of base radius $$R$$ and height $$h$$ is located in a uniform electric field $$\overrightarrow{E}$$ parallel to its base. The electric flux entering the cone is:

Two spherical conductors B and C having equal radii and carrying equal charges in them repel each other with a force F when kept apart at some distance. A third spherical conductor having same radius as that of B but uncharged, is brought in contact with B, then brought in contact with C and finally removed away from both. The new force of repulsion between B and C is:

The magnitude of the average electric field normally present in the atmosphere just above the surface of the Earth is about $$150 N/C$$, directed inward towards the center of the Earth. This gives the total net surface charge carried by the Earth to be : [Given $$\epsilon_0=8.85\times 10^{-12} C^2/N-m^2, R_E=6.4\times 10^6m]$$

Consider two charged metallic spheres $${S}_{1}$$ and $${S}_{2}$$ of radii $${R}_{1}$$ and $${R}_{2}$$ respectively. The electric fields $${E}_{1}$$ (on $${S}_{1}$$) and $${E}_{2}$$ (on $${S}_{2}$$) on their surfaces are such that $${ E }_{ 1 }/{ E }_{ 2 }={ R }_{ 1 }/{ R }_{ 2 }$$. Then the ratio $${V}_{1}$$ (on $${S}_{1}$$)/$${V}_{2}$$ (on $${S}_{2}$$) of the electrostatic potentials on each sphere is:

The electric field in a region of space is given by $$\vec E=E_0\hat i+2 E_o\hat j$$ where $$E_o=100 N/C$$. The flux of this field through a circular surface of radius $$0.02$$ m parallel to the Y-Z plane is nearly :

Three charged particles $$A, B$$ and $$C$$ with charges $$-4q, 2q$$ and $$-2q$$ are present on the circumference of a circle of radius $$d$$. The charged particles $$A, C$$ and centre $$O$$ of the circle formed an equilateral triangle as shown in figure. Electric field at $$O$$ along x-direction is:

Two identical conducting spheres $$A$$ and $$B$$, carry equal charge. They are separated by a distance much larger than their diameter, and the force between them is $$F$$. A third identical conducting sphere, $$C$$, is uncharged. Sphere $$C$$ is first touched to $$A$$, then to $$B$$, and the removed. As a result, the force between $$A$$ and $$B$$ would be equal to

Consider an electric field $$\overline{E}=E_{0}\hat{x}$$, where $$E_{0}$$ is a constant. The flux through the shaded area (as shown in the figure) due to this field is:

Two point charges A and B, having charges +Q and -Q respectively, are placed at certain distance apart and force acting between them is F. If 25% charge of A is transferred to B, then force between the charges becomes

Suppose the charge of a proton and an electron differ slightly. One of them is -e, the other is $$(e+\Delta e)$$. If the net of electrostatic force and gravitational force between two hydrogen atoms placed at a distance d (much greater than atomic size) apart is zero, then $$\Delta e$$ is of the order of [Given mass of hydrogen $$m_h=1.67\times 10^{-27}Kg$$]