In [1]:

```
u=10.*200 # in cm**2/V-s
print "The electron mobility, un = sigma*RH =%0.2f cm**2/V-s"%u
```

In [3]:

```
n=10./((50*10**-4)*(1.6*10**-19)) # m**-3
print "We know that the electron mobilty, un = sigma/nq"
print "Therefore, the electron concentration,"
print " n = sigma / uq =%0.2e m**-3"%n
```

In [4]:

```
n=(1.2*20)/(60*(1.6*10**-19)*(0.5*10**-3)) # in m**3
print "We know that the number of conduction electrons, i.e. electron density,"
print " n = B*I/VH*q*w =%0.2e m**3"%n
```