A charge ${q_1}$ exerts some force on a second charge ${q_2}$. If third charge ${q_3}$ is brought near, the force of ${q_1}$ exerted on ${q_2}$
Decreases
Increases
Remains unchanged
Increases if ${q_3}$ is of the same sign as ${q_1}$ and decreases if ${q_3}$ is of opposite sign
A charge $q$ is placed in the middle of a line joining the two equal and like point charge $Q$. This charge $q$ will remain in equilibrium for which value of $q$ is
The ratio of the forces between two small spheres with constant charge $(a)$ in air $(b)$ in a medium of dielectric constant $K$ is
A particle of mass $1 \,{mg}$ and charge $q$ is lying at the mid-point of two stationary particles kept at a distance $'2 \,{m}^{\prime}$ when each is carrying same charge $'q'.$ If the free charged particle is displaced from its equilibrium position through distance $'x'$ $(x\,< \,1\, {m})$. The particle executes $SHM.$ Its angular frequency of oscillation will be $....\,\times 10^{8}\, {rad} / {s}$ if ${q}^{2}=10\, {C}^{2}$
Two charges each of $1\;coulomb$ are at a distance $1\,km$ apart, the force between them is
Similar charges are placed at corners of a square and a charge $q_0$ is placed at it's centre find net force on it