#importing modules
import math
from __future__ import division
#Variable declaration
EF=8; #fermi energy(eV)
e=1.6*10**-19; #conversion factor from J to eV
m=9.1*10**-31; #mass of electron(kg)
#Calculation
E0bar=3*EF/5;
v=math.sqrt(2*E0bar*e/m); #speed of electron(m/s)
#Result
print "speed of electron is",round(v/10**6,1),"*10**6 m/s"
#importing modules
import math
from __future__ import division
#Variable declaration
I=8; #current(ampere)
r=9*10**-4; #radius(m)
V=5; #potential difference(V)
L=1; #length(m)
#Calculation
A=math.pi*r**2; #area of wire(m**2)
E=V/L;
J=I/A; #current density(V/m)
rho=E/J; #resistivity(ohm m)
#Result
print "current density is",round(J/10**6,3),"*10**6 V/m"
print "resistivity is",round(rho*10**6,2),"*10**-6 ohm m"
#importing modules
import math
from __future__ import division
#Variable declaration
n=1;
a=4*10**-10; #lattice parameter(m)
N=1.56*10**28;
e=1.6*10**-19; #conversion factor from J to eV
tow=10**-15; #collision time(s)
m=9.1*10**-31; #mass of electron(kg)
#Calculation
N=n/(a**3); #number of electrons per unit volume(per m**3)
sigma=N*e**2*tow/m; #conductivity(per ohm m)
rho=1/sigma; #resistivity(ohm m)
#Result
print "conductivity is",round(sigma/10**6,2),"*10**6 ohm m"
print "resistivity is",rho,"ohm m"
#importing modules
import math
from __future__ import division
#Variable declaration
k=1.38*10**-23; #boltzmann constant(J/K)
NA=6.02*10**26; #avagadro number(k/mole)
T=300; #temperature(K)
EF=2; #fermi energy(eV)
e=1.6*10**-19; #conversion factor from J to eV
#Calculation
C=math.pi**2*k**2*NA*T/(2*EF*e); #electronic specific heat(J/kmol/K)
#Result
print "electronic specific heat is",int(C),"J/kmol/K"
#importing modules
import math
from __future__ import division
#Variable declaration
K=327; #thermal conductivity(W/mK)
T=300; #temperature(K)
rho=7.13*10**3; #density(kg/m**3)
NA=6.02*10**26; #avagadro number(k/mole)
w=65.38; #atomic weight
e=1.6*10**-19; #conversion factor from J to eV
tow=2.5*10**-14; #relaxation time(s)
m=9.1*10**-31; #mass of electron(kg)
#Calculation
N=2*rho*NA/w; #number of electrons per unit volume(per m**3)
sigma=N*e**2*tow/m; #conductivity(per ohm m)
L=K/(sigma*T); #lorentz number(W ohm/K**2)
#Result
print "lorentz number is",round(L*10**8,4),"*10**-8 W ohm/K**2"
#importing modules
import math
from __future__ import division
#Variable declaration
e=1.6*10**-19; #conversion factor from J to eV
n=5*10**28; #number of atoms(/m**3)
#Calculation
RH=-1/(n*e); #hall coefficient(m**3/C)
#Result
print "hall coefficient is",round(RH*10**9,3),"*10**-9 m**3/C"