A charge $2\,\mu C$ is taken from infinity to a point in an electric field, without changing its velocity. If work done against forces is $20\,\mu J$ then potential at that point will be.....$V$

Two identical balls having like charges and placed at a certain distance apart repel each other with a certain force. They are brought in contact and then moved apart to a distance equal to half their initial separation. The force of repulsion between them increases $4.5$ times in comparison with the initial value. The ratio of the initial charges of the balls is

In the figure a potential of $+1200\, V$ is given to point $A$ and point $B$ is earthed, what is the potential at the point $P$ ?......$V$

The potential $V$ is varying with $x$ and $y$ as $V = \frac{1}{2}({y^2} - 4x)\,volts$ The field at $(1\,m,\,1\,m)$ is

If the electric potential of the inner shell is $10\,V$ and that of the outer shell is $5\,V$ , then the potential at the centre will be.....$V$

A charge $Q$ is divided into two parts of $q$ and $Q - q$. If the coulomb repulsion between them when they are separated is to be maximum, the ratio of $\frac{Q}{q}$ should be