$12$ positive charges of magnitude $q$ are placed on a circle of radius $R$ in a manner that they are equally spaced. A charge $Q$ is placed at the centre, if one of the charges $q$ is removed, then the force on $Q$ is

  • [KVPY 2010]
  • A

    zero

  • B

    $\frac{q Q}{4 \pi \varepsilon_0 R^2}$ away from the position of the removed charge

  • C

    $\frac{11 q Q}{4 \pi \varepsilon_0 R^2}$ away from the position of the removed charge

  • D

    $\frac{q Q}{4 \pi \varepsilon_0 R^2}$ towards the position of the removed charge

Similar Questions

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

  • [AIEEE 2004]

Why Coulombian force is called two body force ?

Three point charges are placed at the corners of an equilateral triangle. Assuming only electrostatic forces are acting

Two small spheres each having the charge $ + Q$ are suspended by insulating threads of length $L$ from a hook. This arrangement is taken in space where there is no gravitational effect, then the angle between the two suspensions and the tension in each will be

  • [IIT 1986]

Two equally charged, identical metal spheres $A$ and $B$ repel each other with a force '$F$'. The spheres are kept fixed with a distance '$r$' between them. A third identical, but uncharged sphere $C$ is brought in contact with $A$ and then placed at the mid-point of the line joining $A$ and $B$. The magnitude of the net electric force on $C$ is