In [2]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
W=0.1*10**-9; #wavelength of photon(m)
h=6.62*10**-34; #Planck's constant(m^2 Kg/sec)
c=3*10**8; #velocity of light(m/s)
e=1.6*10**-19; #charge of electron(c)
#Calculation
E=h*c/(W*e); #energy of photon(eV)
P=h/W; #momentum of the photon(Kgms^-1)
#Result
print "The energy of photon is",E,"eV"
print "The momentum of the photon is",P,"Kg m s^-1"
```

In [5]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
w=5893*10**-10; #wavelength of emitted light(m)
e=100; #total energy emitted per sec
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
c=3*10**8; #velocity of light(m/s)
#Calculation
E=h*c/w; #energy of one photon(J)
N=e/E; #The total numberof photons emitted(sec)
#Result
print "The total number of photons emitted per second is",round(N/10**20,3),"*10**20 per sec"
print "answer varies due to rounding off errors"
```

In [2]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
w=4000*10**-10; #wavelength in black body(m)
t=1500; #temperature of black body(K)
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
c=3*10**8; #velocity of light(m/s)
Kb=1.38*10**-23; #Boltzmann's constant(m^2 Kg s^-2 k^-1)
#Calculation
Edw=(8*math.pi*h*c/w**5)*(1/(math.exp(h*c/(w*Kb*t))-1)); #The energy density per unit wavelength in a black body cavity(J/m^4)
#Result
print "The energy density per unit wavelength in a black body cavity is",round(Edw,6),"J/m^4"
print "answer varies due to rounding off errors"
```

In [7]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
c=3*10**8; #velocity of light(m/s)
m=9.11*10**-31; #mass of electron(Kg)
#Calculation
w=h/(c*m)*10**10; #The compton wavelength for an electron(Armstrong)
#Result
print "The compton wavelength for an electron is",round(w,4),"Angstrom"
```

In [10]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
theta=90; #x ray photon scattered at a angle(degrees)
h=6.625*10**-34; #Planck's constant(J-sec)
c=3*10**8; #velocity of light(m/s)
m=9.11*10**-31; #mass of electron(Kg)
#Calculation
theta=theta*math.pi/180; #angle(radian)
deltalamda=((h/(c*m))*(1-math.cos(x)))/10**-10; #The change in wavelength for Xray photon(Angstrom)
#Result
print "The change in wavelength for X ray photon is",round(deltalamda,4),"Angstrom"
```

In [12]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
theta=180; #x ray carbon scattered at a angle(degrees)
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
c=3*10**8; #velocity of light(m/s)
m=9.11*10**-31; #mass of electron(kg)
v=1.8*10**18; #frequency of incident rays(s^-1)
#Calculation
theta=theta*math.pi/180; #angle(radian)
w=c/v; #wavelength(m)
tw=(h/(c*m))*(1-math.cos(theta)); #The change wavelength for Xray carbon(m)
lamda_dash=(w+tw)/10**-10; #The wavelength of X-rays carbon(Angstrom)
#Result
print "The wavelength of X-rays carbon is",round(lamda_dash,2),"Angstrom"
```

In [17]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
w=3*10**-10; #wavelength of incident photons(m)
theta=60; #angle of view(degrees)
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
c=3*10**8; #velocity of light(m/sec)
m=9.11*10**-31; #mass of electron(Kg)
#Calculation
theta=theta*math.pi/180; #angle(radian)
lamda_dash=(w+((h/(c*m))*(1-math.cos(theta))))/10**-10; #The wavelength of scattered photons(Angstrom)
#Result
print "The wavelength of scattered photons is",round(lamda_dash,3),"Angstrom"
```

In [3]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
x=4; #Total energy increase to 4 times of its initial rest energy
c=3*10**8; #velocity of light(m/sec)
#Calculation
v=math.sqrt(c**2*(1-(1/x**2))); #The Velocity of moving electron(m/sec)
#Result
print "The Velocity of moving electron is",round(v/10**8,4),"*10**8 m/sec"
```

In [5]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
a=0.1*10**-9; #width of high potential box(m)
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
m=9.11*10**-31; #mass of electron(Kg)
e=1.6*10**-19; #charge of electron(c)
n=1; #take n equal to one
#Calculation
E=(n**2*h**2)/(8*m*a**2*e); #The least energy of the particle can be obtained(eV)
#Result
print "The least energy of the particle can be obtained is",round(E,3),"eV"
print "answer varies due to rounding off errors"
```

In [8]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
a=10**-14; #length of impenerable box(m)
m=1.67*10**-27; #mass of neutron(Kg)
n=1; #for lowest energy
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
#Calculation
E=(n**2*h**2)/(8*m*a**2); #The least energy of the neutron can be obtained(J)
#Result
print "The least energy of the neutron can be obtained is",round(E/(1.6*10**-19*10**6),3),"MeV"
```

In [10]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
a=4*10**-10; #width of electron box(m)
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
m=9.11*10**-31; #mass of electron(kg)
e=1.6*10**-19; #charge of electron(c)
n=1; #first permitted level
#Calculation
E1=((n**2*h**2)/(8*m*a**2*e)); #The first permitted energy level by taking n=1(eV)
E2=4*E1; #The second permitted energy level by taking n=2(eV)
E3=9*E1; #The third permitted energy level by taking n=3(eV)
#Result
print "The first permitted energy level by taking n=1 is",round(E1,3),"eV"
print "The second permitted energy level by taking n=2 is",round(E2,2),"eV"
print "The third permitted energy level by taking n=3 is",round(E3,3),"eV"
print "answer varies due to rounding off errors"
```

In [12]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
a=1.5*10**-10; #each side of cubical box(m)
n1=1; #for lowest energy
n2=1; #for lowest energy
n3=1; #for lowest energy
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
m=9.11*10**-31; #mass of electron(Kg)
e=1.6*10**-19; #charge of electron(c)
#Calculation
n=(n1**2+n2**2+n3**2); #total value of n
E=((n*h**2)/(8*m*a**2*e)); #The lowest energy of electron ina cubical box(eV)
#Result
print "The lowest energy of electron in a cubical box is",round(E,3),"eV"
```

In [16]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
a=4*10**-9; #width of potential well(m)
n=1; #For minimum energy n value
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
m=9.11*10**-31; #mass of electron(Kg)
e=1.6*10**-19; #charge of electron(c)
#Calculation
E=((n**2*h**2)/(8*m*a**2*e)); #The lowest energy of electron in deep potential well(eV)
#Result
print "The lowest energy of electron in deep potential well is",round(E,5),"eV"
```

In [18]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
a=0.1*10**-9; #length of one dimensional box(m)
n=1; #first permitted level
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
m=9.11*10**-31; #mass of electron(kg)
e=1.6*10**-19; #charge of electron(c)
#Calculation
E1=((n**2*h**2)/(8*m*a**2*e)); #The ground state of electron in an one dimensional box(eV)
E6=36*E1; #The fifth exited state of electron(eV)
E=E6-E1; #The energy required the electron from its ground state to the fifth exited state(eV)
#Result
print "The energy required the electron from its ground state to the fifth exited state is",int(E),"eV"
```

In [20]:

```
#importing modules
import math
from __future__ import division
#Variable declaration
a=0.1*10**-9; #length of one dimensional box(m)
n=1; #first permitted level
h=6.625*10**-34; #Planck's constant(m^2 Kg/sec)
m=9.11*10**-31; #mass of electron(Kg)
e=1.6*10**-19; #charge of electron(c)
ne=3; #the number of electrons
#Calculation
E=((n**2*h**2)/(8*m*a**2*e))*ne; #The lowest energy of the system consisting of three electron ia a one dimensional box(eV)
#Result
print "The lowest energy of the system consisting of three electron ia a one dimensional box is",round(E,4),"eV"
print "answer varies due to rounding off errors"
```