# 2: Electrostatics-II¶

## Example number 2.1, Page number 47¶

In :
#importing modules
import math
from __future__ import division

#Variable declaration
dV=8*10**7;      #potential on cloud(V)
dx=500;    #height(m)

#Calculation
E=dV/dx;     #electric field intensity(V/m)

#Result
print "electric field intensity is",E/10**4,"*10**4 V/m"

electric field intensity is 16.0 *10**4 V/m


## Example number 2.2, Page number 47¶

In :
#importing modules
import math
from __future__ import division

#Variable declaration
dV=8000;      #potential difference(V)
dx=0.2;    #height(m)
q=5*10**-9;    #positive charge(C)

#Calculation
E=dV/dx;     #electric field intensity(V/m)
F=q*E;    #force acting(N)

#Result
print "force acting is",F*10**4,"*10**-4 N"

force acting is 2.0 *10**-4 N


## Example number 2.3, Page number 47¶

In :
#importing modules
import math
from __future__ import division

#Variable declaration
e=1.6*10**-19;     #charge on proton(C)
z=79;    #atomic number of gold
#let x=1/(4*pi*epsilon0)
x=9*10**9;
r=6.6*10**-15;   #radius(m)

#Calculation
q=z*e;    #charge on gold nucleus(C)
V=x*q/r;   #potential(V)

#Result
print "potential is",round(V/10**6,1),"*10**6 V"

potential is 17.2 *10**6 V


## Example number 2.4, Page number 47¶

In :
#importing modules
import math
from __future__ import division

#Variable declaration
theta1=0;    #angle on axis(radian)
theta2=90;   #angle on perpendicular bisector(degree)
r=1;   #distance(m)
p=4.5*10**-10;   #dipole moment(C/m)
#let x=1/(4*pi*epsilon0)
x=9*10**9;

#Calculation
theta2=theta2*math.pi/180;     #angle on perpendicular bisector(radian)
V1=x*p*math.cos(theta1)/(r**2);    #electric potential on axis(V)

#Result
print "electric potential on axis is",V1,"V"
print "electric potential on perpendicular bisector is 0 V"

electric potential on axis is 4.05 V
electric potential on perpendicular bisector is 0 V