chapter 06 : X Rays

Ex6.1 : : Pg: 156

In [1]:
#Wavelength of X-rays
h = 6.6e-034     # Planck's constant, J-s
V = 50000     # Potential difference, volts
c = 3e+08     # Velocity of light, m/s
e = 1.6e-019     # Charge of an electron, coulombs
L_1 = h*c/(e*V)     # wavelength of X-rays, m
L = L_1/1e-010     # wavelength of X-rays, angstorm
print "The shortest wavelength of X-rays = %6.4f angstorm"% L  

The shortest wavelength of X-rays = 0.2475 angstorm

Ex6.2 : : Pg: 156

In [3]:
#Planck's constant
L = 24.7e-012     # Wavelength of X-rays, m
V = 50000     # Potential difference, volts
c = 3e+08     # Velocity of light, m/s
e = 1.6e-019     # Charge of an electron, coulombs
# Since e*V = h*c/L     # Energy required by an electron to move through a potential barrier of one volt, joules
# solving for h
h = e*V*L/c     # Planck's constant, Joule second
print "h = %3.1e Js "% h  

h = 6.6e-34 Js

Ex6.3 : : Pg: 156

In [5]:
#Short wavelength limit 
V = 50000     # Potential difference, volts
h = 6.624e-034     # Planck's constant, Js
c = 3e+08     # Velocity of light, m/s
e = 1.6e-019     # Charge of an electron, coulombs
# Since e*V = h*c/L     # Energy required by an electron to move through a potential barrier of one volt, joules
# solving for L
L = h*c/(e*V)     # Short wavelength limit of X-ray, m
print "Short wavelength limit of X-ray = %6.4f angstorm"% (L/1e-010) 

Short wavelength limit of X-ray = 0.2484 angstorm

Ex6.4 : : Pg: 157

In [6]:
#Wavelength limit of X-rays 
V = 20000     # Potential difference, volt
h = 6.624e-034     # Planck's constant, Js
c = 3e+08     # Velocity of light, m/s
e = 1.6e-019     # Charge of an electron, coulombs
# Since e*V = h*c/L     # Energy required by an electron to move through a potential barrier of one volt, joules
# solving for L
L = h*c/(e*V)     # Wavelength limit of X-rays, m
print "Short wavelength limit of X-ray = %6.4f angstorm"% (L/1e-010) 

Short wavelength limit of X-ray = 0.6210 angstorm

Ex6.5 : : Pg: 157

In [8]:
#Minimum voltage of an X-ray tube 
h = 6.625e-034     # Planck's constant, Js
c = 3e+08     # Velocity of light, m/s
e = 1.6e-019     # Charge of an electron, coulombs
L = 1e-010     # Wavelength of X-rays, m
# Since e*V = h*c/L     # Energy required by an electron to move through a potential barrier of one volt, joules
# solving for V
V = h*c/(L*e)     # Potential difference, volts
print "The minimum voltage of an X-ray tube = %5.2f kV"% (V/1e+03) 

The minimum voltage of an X-ray tube = 12.42 kV

Ex6.6 : : Pg: 157

In [10]:
#Minimum wavelength emitted by an X-ray tube 
h = 6.625e-034     # Planck's constant, Js
c = 3e+08     # Velocity of light, m/s
e = 1.6e-019     # Charge of an electron, coulombs
V = 4.5e+04     # Accelerating potential of X-ray tube, volt
# Since e*V = h*c/L_min     # Energy required by an electron to move through a potential barrier of one volt, joules
# solving for L_min
L_min = h*c/(V*e)     # Minimum wavelength emitted by an X-ray tube, m
print "The minimum wavelength emitted by the X-ray tube = %5.3f angstrom"% (L_min/1e-010) 

The minimum wavelength emitted by the X-ray tube = 0.276 angstrom

Ex6.7: : Pg: 158

In [11]:
#Critical voltage for stimualted emission 
h = 6.625e-034     # Planck's constant, Js
c = 3e+08     # Velocity of light, m/s
e = 1.6e-019     # Charge of an electron, coulombs
L_k = 0.178e-010     # Wavelength of k absorption egde of X-rays, m
# Since e*V_critical = h*c/L     # Energy required by an electron to move through a potential barrier of one volt, joules
# solving for V_critical
V_critical = h*c/(L_k*e)     # Crtical voltage for stimulated enission, volt
print "The critical voltage for stimulated emission = %4.1f kV"% (V_critical/1e+03) 

The critical voltage for stimulated emission = 69.8 kV