A spherical cavity of radius $r$ is made inside a solid uncharged conducting sphere of radius $R$ and a charge $q$ is placed inside the cavity at its centre. A point charge $q_1$ is placed outside the sphere at a distance '$a$' from centre of the sphere, as shown. point $A$ is inside the sphere (at a distance $x$ from centre of the sphere) and point $B$ is inside the cavity ( at $a$ distance $y$ from centre of cavity). $\left[K=\frac{1}{4\pi {\epsilon }_0}\right]$.

 

Choose the correct statement(s)

The work done to assemble the three charges in a configuration as shown in the figure below is

A point particle of mass $0.5 \mathrm{kg}$ is moving along the $X$ -axis under a force described by the potential energy $V$ shown below. It is projected towards the right from the origin with a speed $v$.

What is the minimum value of $v$ for which the particle will escape infinitely far away from the origin?

A two point charges $4q$ and $–q$ are fixed on the $x$ -axis at $x=\frac{-d}{2}$ and $x=\frac{d}{2}$, respectively. If the third point charge ‘$q$ ’ is taken from the origin to $x=d$ along the semicircle as shown in the figure, the energy of the charge will:

The diagrams below show regions of equipotential.



A positive charge is moved from $A$ to $B$ in each diagram.