#importing modules
import math
from __future__ import division
#Variable declaration
k=1.38*10**-23; #boltzmann constant(J)
T=300; #temperature(K)
e=1.6*10**-19; #charge(c)
#Calculation
E=3*k*T/(2*e); #average thermal energy(eV)
#Result
print "average thermal energy is",round(E,3),"eV"
#importing modules
import math
from __future__ import division
#Variable declaration
kT=1; #assume
E_Ef=kT;
#Calculation
FE=1/(1+math.exp(1)); #fermi function
#Result
print "fermi function is",round(FE,3)
#importing modules
import math
from __future__ import division
#Variable declaration
FE=10/100; #fermi function
EF=5.5; #energy function(eV)
e=1.6*10**-19; #charge(c)
k=1.38*10**-23; #boltzmann constant(J)
#Calculation
E=EF+(EF/100); #energy(eV)
x=math.log((1/FE)-1);
T=(E-EF)*e/(k*x); #temperature(K)
#Result
print "temperature is",round(T,1),"K"
#importing modules
import math
from __future__ import division
#Variable declaration
k=1.38*10**-23; #boltzmann constant(J)
T=24600; #temperature(K)
m=9.108*10**-31; #mass(kg)
#Calculation
vF=math.sqrt(2*k*T/m); #fermi velocity(m s-1)
#Result
print "fermi velocity is",round(vF/10**6,2),"*10**6 m s-1"
#importing modules
import math
from __future__ import division
from scipy.integrate import quad
#Variable declaration
EF=3.0; #fermi energy(eV)
e=1.6*10**-19; #charge(c)
m=9.14*10**-31; #mass(kg)
h=6.62*10**-34; #planck's constant
#Calculation
E1=EF*e; #energy(J)
E2=(EF+0.01)*e; #energy(J)
def zintg(E):
return (4*math.pi*(2*m)**(3/2)*math.sqrt(E))/h**3;
n=quad(zintg,E1,E2)[0]; #number of states
#Result
print "number of states is",round(n/10**26,4),"*10**26"
print "answer given in the book is wrong"