The equation of an equipotential line in an electric field is $y = 2x$. The electric field strength vector at $(1, 2)$ may be:

The figure shows lines of constant potential in a region where an electric field is present. The electric field at point $B$ is............

$A$ metallic sphere has a charge of $10\,\mu C$. $A$ unit negative charge is brought from $A$ to $B$,both $100\,cm$ away from the sphere,with $A$ being east of it and $B$ being west of it. The net work done is........$joule$.

If a unit charge is taken from one point to another point over an equipotential surface,then

There is $10$ units of charge at the centre of a circle of radius $10\,m$. The work done in moving $1\,unit$ of charge around the circle once is...........$units$.

As per the diagram,a point charge $+q$ is placed at the origin $O$. The work done in taking another point charge $-Q$ from point $A$ [coordinates $(0, a)$] to point $B$ [coordinates $(a, 0)$] along the straight path $AB$ is: