Two fixed charges $4\,Q$ (positive) and $Q$ (negative) are located at $A$ and $B$, the distance $AB$ being $3$ $m$.
The point $P$ where the resultant field due to both is zero is on $AB$ outside $AB$.
If a negative charge is placed at $P$ and displaced slightly along $AB $ it will execute oscillations.
If a positive charge is placed at $P$ and displaced slightly along $AB$ it will execute oscillations.
$A$ and $B$ both
Two charges ${q_1}$ and ${q_2}$ are placed in vacuum at a distance $d$ and the force acting between them is $F$. If a medium of dielectric constant $4$ is introduced around them, the force now will be
Write value of Coulombian constant $k$ in $SI$ unit.
A $10\,\mu C$ charge is divided into two parts and placed at $1\,cm$ distance so that the repulsive force between them is maximum. The charges of the two parts are :
Force between two identical spheres charged with same charge is $F$. If $75\%$ charge of one sphere is transfered to the other sphere then the new force will be
A proton is fired at an initial velocity of $150 \,m/s$ at an angle of $60^o $ above the horizontal into a uniform electric field of $2 \times 10^{-4} \,N/C$ between two charged parallel plates as shown in figure. Then the total time the particle is in motion is :-