Two similar spheres having $ + \,q$ and $ - \,q$ charge are kept at a certain distance. $F$ force acts between the two. If in the middle of two spheres, another similar sphere having $ + \,q$ charge is kept, then it experience a force in magnitude and direction as
Zero having no direction
$8F$ towards $ + \,q$ charge
$8F$ towards $ - \,q$ charge
$4F$ towards $ + \,q$ charge
Two point charges $ + 3\,\mu C$ and $ + 8\,\mu C$ repel each other with a force of $40\,N$. If a charge of $ - 5\,\mu C$ is added to each of them, then the force between them will become....$N$
Three charges are placed at the vertices of an equilateral triangle of side ‘$a$’ as shown in the following figure. The force experienced by the charge placed at the vertex $A$ in a direction normal to $BC$ is
Two identical pendulum $A$ and $B$ are suspended from the same point. The bobs are given positive charges, with $A$ having more charge than $B$ . They diverge and reach at equilibrium, with $A$ and $B$ making angles $\theta _1$ and $\theta _2$ with the vertical respectively, Then
Two point charges $ + 9e$ and $ + e$ are at $16\, cm$ away from each other. Where should another charge $q$ be placed between them so that the system remains in equilibrium
Two equal negative charges are fixed at the points $ [0, a ]$ and $[0, -a]$ on the $y-$ axis. A positive charge $Q$ is released from rest at the points $[2a, 0]$ on the $x-$axis . The charge $Q$ will