B M Sharma Solutions for Chapter: Coulomb's Laws and Electric Field, Exercise 2: DPP

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 experiences a force in magnitude and direction as

Point charges $+4q$, $-q$ and $+4q$ are kept on the $x$-axis at points $X=0$, $X=a$ and $X=2a$, respectively, then

Two identical balls having like charges and placed at a certain distance apart repel each other with a certain force. They are brought in contact and then moved apart to a distance equal to half their initial separation. The force of repulsion between them increases $4.5$ times in comparison with the initial value. The ratio of the initial charges of the balls is

Two charges $+4e$ and $+e$ are at a distance $x$ apart. At what distance, a charge $q$ must be placed from charge $+e$ so that it is in equilibrium?

Charges $4Q, q$ and $Q$ and placed along $x$-axis at positions $x=0, x=1/2$ and $x=1,$ respectively. Find the value of $q$ so that the force on charge $Q$ is zero.

Two equal negative charges $-q$ are fixed at points $(0,a)$ and $(0.-a)$ on the y-axis. A positive charge $Q$ is released from rest at the point $(2a,0)$ on the x-axis. The charge $Q$ will

Two free point charges $+q$ and $+4q$ are placed a distance $x$ apart. A third charge is so placed that all the three charges are in equilibrium. Then

If two balls of given masses and charges suspended from the same point are released, which of the following is the correct arrangement in equilibrium?