In [1]:

```
from math import *
#Variable declaration
H_0 = 1; # Amplitude off field vector,in A/m
mu_0 = 12.56e-7; # Permeability,in weber/A-m
eps = 8.85e-12; # Permittivity in free space,in C/N-meter-square
#Calculations
# From the relation between the amplitude of the field vector E and vector H of an EM wave in free space
E_0 = H_0*(sqrt(mu_0/eps));
#Result
print "The amplitude of field vector E in free space = %5.1f V/m"%E_0
```

In [2]:

```
#Variable declaration
E_o = 1e+3; # Amplitude field vector in free space,N/C
c = 3e+8; # Speed of light,in m/s
#Calculations
# From the relation between the amplitude of the field vector E and vector H of an EM wave in free space E_o = H_o*(sqrt(mu_o/eps))and B_o = mu_o*H_o, we have
B_o = E_o/c;
#Result
print "The maximum value of magnetic induction vector = %4.2e weber/A-m"%B_o
```

In [3]:

```
#Variable declaration
sigma = 5; # Conductivity of the conducting medium, mho/m
eps_r = 8.85e-12; # Relative electrical permittivity of medium, F/m
eps_0 = 1; # Electrical permittivity of free space, F/m
E0 = 250; # Amplitude of applied electric field, V/m
#Calculations
J = sigma*E0; # Amplitude of conduction current density, A/metre-square
J_D = eps_r*eps_0*E0*1e+010; # Amplitude of displacement current density, A/metre-square
omega = sigma/(eps_0*eps_r); # Frequency at which J = J_D
#Results
print "The conduction current density = %3dsin(10^10t) A/metre-quare"%J
print "The displacement current density = %5.3fcos(10^10t) A/metre-quare"%J_D #incorrect answer in the textbook
print "The frequency at which J = J_D is %3.1e Hz"%omega
```

In [4]:

```
from math import *
#Variable declaration
P = 1000; # Energy radiated by the lamp, watt
r = 2; # Distance from the source at which the electric field intensity is given, m
#Calculations
S = P/(4*pi*r**2); # Magnitude of Poynting vector, W/metre-square
# As wave imepdence, Z0 = E/H = 377 and H = E/377, so that with E*H = S we have
E = 377
E = sqrt(S*E)
#Result
print "The average value of the intensity of electric field of radiation = %4.1f V/m"%(E)
```

In [5]:

```
from math import *
#Variable declaration
S = 2*4.186/60*1e+04; # Solar constant, J/s/metre-square
# From the poynting vector S = E*H
C = 377; # Wave Impedence, ohm
#Calculations
E = sqrt(S*C); # Electric field of radiation, V/m
H = E/C; # Magnetic field of radiation, A/m
E0 = E*sqrt(2); # Amplitude of electric field of radiation, V/m
H0 = H*sqrt(2); # Amplitude of magnetic field of radiation, A/m
#Results
print "The amplitude of electric field of radiation = %6.1f V/m"%E0 #incorrect answer in the textbook
print "The amplitude of magnetic field of radiation = %5.3f V/m"%H0
```

In [6]:

```
from math import *
#Variable declaration
sigma = 3.54e+007; # Electrical conductivity of Al, mho per metre
mu = 12.56e-007; # Permeability of the medium, weber/A-m
f = 71.6e+06; # Frequency of the wave, Hz
#Calculations
omega = 2*pi*f; # Angular frequency of the wave, rad per sec
delta = sqrt(2/(sigma*mu*omega)); # Skin depth of the EM wave in Al, m
#Result
print "The skin depth of an EM-wave in Al = %2.0f micron"%(delta/1e-06)
```

In [8]:

```
from math import *
#Variable declaration
sigma = 5.; # Electrical conductivity, mho per metre
mu = 12.56e-007; # Permeability of the medium, weber/A-m
eps_0 = 8.85e-012; # Electric permittivity of free space, C-square/N-m-square
#Calculations&Results
eps = 70*eps_0; # Electric permittivity of the medium, C-square/N-m-square
delta = 2/sigma*sqrt(eps/mu); # The skin depth and attenuation constant of sea water
print "The skin depth of an EM-wave in sea water = %6.4f m"%delta
Beta = 1/delta; # The attenuation constant of sea water, per metre
print "The attenuation constant of the sea water = %6.2f m"%Beta
```