In crystals of the salt cesium chloride. cesium ions $\left({\mathrm{Cs}}^{+}\right)$ form the eight corners of a cube and a chlorine ion $\left({\mathrm{Cl}}^{-}\right)$ is at the cube's center. The edge length of the cube is $0.40 \mathrm{nm}$. $\left({\mathrm{Cs}}^{+}\right)$ ions are each deficient by one electron (thus each has a charge $+e$), and the $\left({\mathrm{Cl}}^{-}\right)$ ion has one excess electron (thus has a charge $-e$).

$\left(A\right)$ What is the magnitude of the net electrostatic force exerted on the $\left({\mathrm{Cl}}^{-}\right)$ ion by the eight $\left({\mathrm{Cs}}^{+}\right)$ ions at the corners of the cube?

$\left(B\right)$ If one of the $\left({\mathrm{Cs}}^{+}\right)$ ions is missing, the crystal is said to have a defect. What is the magnitude of the net electrostatic force exerted on the $\left({\mathrm{Cl}}^{-}\right)$ ion by the seven remaining $\left({\mathrm{Cs}}^{+}\right)$ ions? 

Two particles are fixed on $x-$axis. Particle $\left(1\right)$ of charge $50 \mathrm{\mu C}$ is located at $x=-2.0 \mathrm{cm}$, particle $\left(2\right)$ of charge $Q$ is located at $x=3.0 \mathrm{cm}$ and particle $\left(3\right)$ of charge magnitude $20 \mathrm{\mu C}$ is released from rest on the $y-$axis at $y=2.0 \mathrm{cm}$. What is the value of $Q$, if the initial acceleration of particle $\left(3\right)$ is in the positive direction of the 

$\left(A\right)$ $x-$axis

$\left(B\right)$ $y-$axis

Calculate the number of coulombs of positive charge in $500$ ${\mathrm{cm}}^3$ of (neutral) water.

(A hydrogen atom contains one proton and an oxygen atom contains eight protons.)

Electrons and positrons are produced by the nuclear transformations of protons and neutrons, respectively. The process is termed as beta decay.

$\left(A\right)$ If a proton transforms to a neutron, then is an electron or a positron produced?

$\left(B\right)$ If a neutron transforms to a proton, then is an electron or a positron produced?

Particles $\left(1\right)$ and $\left(2\right)$ of charge $q_1=q_2=+4e$ are on $y$-axis at distance $d=17.0 \mathrm{cm}$ from the origin. Particle $\left(3\right)$ of charge $q_3=+8e$ is moved gradually along the $x$-axis from $x=0$ to $x=+5.0 \mathrm{m}$. At what values of $x$, will the magnitude of the electrostatic force on the third particle from the other two particles be 

$\left(A\right)$ minimum?

$\left(B\right)$ maximum?

What is the

$\left(C\right)$ minimum magnitude?

$\left(D\right)$ maximum magnitude? 

In the figure, particle $1$ (of charge $q_1$) and particle $2$ (of charge $q_2$) are fixed in place, on the $x$-axis, $8.00 \mathrm{cm}$ apart. Particle $3$ $($of charge $q_{3 }=+6.00\times {10}^{-19} \mathrm{C}$) is to be placed on the line between particles $1$ and $2$, so that they produce a net electrostatic force ${\overrightarrow{F}}_{3,\mathrm{net}}$ on it. Figure gives the $x$-component of that force versus the coordinate $x$, at which particle $3$ is placed. The scale of the $x$-axis is set by $x_{\mathrm{n}}=8.0 \mathrm{cm}$. What are $\left(\mathrm{a}\right)$ the sign of charge $q_1$ and $\left(\mathrm{b}\right)$ the ratio $\frac{q_2}{q_1}$? 

A particle of charge $3.00 \mathrm{\mu C}$ is separated by $0.120 \mathrm{m}$ from a particle of charge $-1.50 \mathrm{\mu C}$.

$\left(\mathrm{a}\right)$ What is the magnitude of the electrostatic force between them? $\left(\mathrm{b}\right)$ What must their separation be reduced that force is of an order of magnitude $10$?

The figure shows an arrangement of four charged particles, with angle $\theta =35.0°$ and distance $d=2.00 \mathrm{cm}$. Particle $2$ has charge $q_2$$=+8.00\times {10}^{-19 }\mathrm{C}$, particles $3$ and $4$ have charges $q_3=q_4=-1.60\times {10}^{-19} \mathrm{C}$.
$\left(\mathrm{a}\right)$ What is distance $D$ between the origin and particle $2$ if the net electrostatic force on particle $1$ due to the other particles is zero? 

$\left(\mathrm{b}\right)$ If particles $3$ and $4$ were moved closer to the $x$-axis but maintained their symmetry about that axis, would the required value of $D$ be greater than, less than, or the same as in part $\left(\mathrm{a}\right)$? 

In the given figure, three charged particles lie on an $x$-axis. Particles $1$ and $2$ are fixed in place. Particle $3$ is free to move, but the net electrostatic force on it from particles $1$ and $2$ happens to be zero. If  $2L_{23 }=L_{12},$ what is the ratio $\frac{{\mathrm{q}}_1}{{\mathrm{q}}_2}$?