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
If $g_E$ and $g_M$ are the accelerations due to gravity on the surfaces of the earth and the moon respectively and if Millikan's oil drop experiment could be performed on the two surfaces, one will find the ratio (electronic charge on the moon/electronic charge on the earth) to be
Write Coulomb’s law and explain its scalar form.
Two identical non-conducting thin hemispherical shells each of radius $R$ are brought in contact to make a complete sphere . If a total charge $Q$ is uniformly distributed on them, how much minimum force $F$ will be required to hold them together
A particle of charge $-q$ and mass $m$ moves in a circle of radius $r$ around an infinitely long line charge of linear density $+\lambda$. Then time period will be given as
(Consider $k$ as Coulomb's constant)
When ${10^{14}}$ electrons are removed from a neutral metal sphere, the charge on the sphere becomes......$\mu C$