A conducting sphere of radius $R$ and charge $Q$ is placed near a uniformly charged nonconducting infinitely large thin plate having surface charge density $\sigma$. Then find the potential at point $A$ (on the surface of sphere) due to charge on sphere (here $K=\frac{1}{4\pi {\epsilon }_0}$, ${\theta }_0=\frac{\pi }{3}$) 

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A spherical conductor $A$ is placed concentrically inside a hollow spherical conductor $B$. The charge $+Q$ is given to $A$ and $B$ is earthed. Then the electric field is not zero

Write any five application of superconductors.

Conventionally which coloured wire is used for earthing?

Three concentric spherical shells are arranged as shown in the figure. The innermost and outermost spheres are connected to earth. If the middle sphere is given a charge $q_0$. the charges induced in the innermost and outermost spheres respectively are

Two long concentric hollow metallic cylinders of radii$a$and$b$, respectively carry equal and opposite charges $-\sigma$ and $+\sigma$ per unit length, as shown. The space between the cylinders is filled with air. The distance measured from the central axis is denoted by $r.$

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Which of the following statements is NOT CORRECT?

Given below are two statements.
Statement I : Electric potential is constant within and at the surface of each conductor.

Statement II : Electric field just outside a charged conductor is perpendicular to the surface of the conductor at every point.

In the light of the above statements, choose the most appropriate answer from the options give below.

A hollow conducting sphere is placed in an electric field produced by a point charge placed at $P$ as shown in figure. Let $V_A, V_B, V_C$ be the potentials at points $A, B$ and $C$, respectively. Then

Consider an initially neutral hollow conducting spherical shell with inner radius $r$ and outer radius $2r.$ A point charge $+Q$ is now placed inside the shell at a distance $\frac{r}{2}$ from the center. The shell is then grounded by connecting the outer surface to the earth. P is an external point at a distance $2r$ from the point charge $+Q$ on the line passing through the center and the point charge $+Q$ as shown in the figure.



The magnitude of the force on a test charge $+q$ placed at P will be

In a system used for spraying cars, a car body is positively charged. Neutral conducting droplets of paint are then attracted to the car because the positive car body induces charge on the droplets of paint. Which diagram best shows the charge pattern ?

Assertion: When a charged body is brought near a neutral conducting body, the induced charge that appears on the nearer surface of the conducting body is always equal and opposite to the charge that has been brought near to it.

Reason: Net electric field inside the conductor is zero.