In [1]:

```
import math
#Variables
IE = 10 #Emitter current (in milli-Ampere)
IC = 9.8 #Collector current (in milli-Ampere)
#Calculation
IB = IE - IC #Base current (in milli-Ampere)
#Result
print "Base current is ",IB," mA."
```

In [2]:

```
import math
#Variables
IE = 6.28 #Emitter current (in milli-Ampere)
IC = 6.20 #Collector current (in milli-Ampere)
#Calculation
alpha = IC / IE #Common base current gain
#Result
print "Common-Base current gain is ",round(alpha,3),"."
```

In [3]:

```
import math
#Variables
alpha = 0.967 #common base current gain
IE = 10 #Emitter current (in milli-Ampere)
#Calculation
IC = alpha * IE #Collector current (in milli-Ampere)
IB = IE - IC #Base current (in milli-Ampere)
#Result
print "Base current is ",IB," mA."
```

In [4]:

```
import math
#Variables
IE = 10 #Emitter current (in milli-Ampere)
alpha = 0.987 #common base current gain
#Calculation
IC = alpha * IE #Collector current (in milli-Ampere)
IB = IE - IC #Base current (in milli-Ampere)
#Result
print "IC is ",IC," mA.\nIB is ",IB," mA."
```

In [5]:

```
import math
#Variables
alpha1 = 0.975 #common base current gain
beta1 = 200.0 #common emitter current gain
#Calculation
beta = alpha1 / (1-alpha1) #common emitter current gain
alpha = beta1 / (beta1 + 1) #common base current gain
#Result
print "Value of beta when alpha = 0.975 is ",beta,".\nValue of alpha when beta = 200 is ",round(alpha,3),"."
```

In [6]:

```
import math
#Variables
beta = 100.0 #common emitter current gain
IC = 40.0 #Collector current (in milli-Ampere)
#Calculation
IB = IC / beta #Base current (in milli-Ampere)
IE = IB + IC #Emitter current (in milli-Ampere)
#Result
print "The value of emitter current is ",IE," mA."
```

In [7]:

```
import math
#Variables
beta = 150.0 #common emitter current gain
IE = 10 #Emitter current (in milli-Ampere)
#Calculation
alpha = beta / (beta + 1) #common base current gain
IC = alpha * IE #Collector current (in milli-Ampere)
IB = IE - IC #Base current (in milli-Ampere)
#Result
print "Collector current is ",round(IC,2)," mA.\nBase current is ",round(IB,2)," mA."
```

In [8]:

```
import math
#Variables
beta = 170.0 #common emitter current gain
IC = 80.0 #Collector current (in milli-Ampere)
#Calculation
IB = IC / beta #Base current (in milli-Ampere)
IE = IB + IC #Emitter current (in milli-Ampere)
#Result
print "Base current is ",round(IB,2)," mA.\nEmitter current is ",round(IE,2)," mA."
```

In [9]:

```
import math
#Variables
IB = 0.125 #Base current (in milli-Ampere)
beta = 200.0 #common emitter current gain
#Calculation
IC = IB * beta #Collector current (in milli-Ampere)
IE = IC + IB #Emitter current (in milli-Ampere)
#Result
print "Value of collector current is ",IC," mA.\nValue of emitter current is ",IE," mA."
#Correction in book . The Value of IB is 0.125 mA.
```

In [10]:

```
import math
#Variables
IE = 12.0 #Emitter current (in milli-Ampere)
beta = 140.0 #common emitter current gain
#Calculation
IB = IE / (1 + beta) #Base current (in milli-Ampere)
IC = IE - IB #Collector current (in milli-Ampere)
#Result
print "Collector current is ",round(IC,3)," mA.\nBase current is ",round(IB,3)," mA."
```

In [11]:

```
import math
#Variables
IB = 105 * 10**-3 #Base current (in milli-Ampere)
IC = 2.05 #Collector current (in milli-Ampere)
#Calculation
beta = IC / IB #Common base current gain
alpha = beta / (1 + beta) #Common emitter current gain
IE = IB + IC #Emitter current (in milli-Ampere)
IC1 = IC + 0.65 #New collector current (in milli-Ampere)
IB1 = IB + 27 * 10**-3 #New base current (in milli-Ampere)
beta1 = IC1 / IB1 #New value of beta
#Result
print "Beta of the transistor is ",round(beta,1),".\nalpha of the transistor is ",round(alpha,2),".\nEmitter current is ",IE," mA.\nNew value of beta is ",round(beta1,2),"."
#Correction to be done in book in value of IB . IB is in micro - Ampere in both initial and in the changed condition. In calculation proper conversion has been done.
```

In [12]:

```
import math
#Variables
alpha = 0.98 #common base current gain
ICO = 5 * 10**-3 #Leakage current (in milli-Ampere)
IB = 100 * 10**-3 #Base current (in milli-Ampere)
#Calculation
IC = (alpha * IB + ICO)/ (1 - alpha) #Collector current (in milli-Ampere)
IE = IC + IB #Emitter current (in milli-Ampere)
#Result
print "Value of collector current is ",IC," mA.\nValue of emitter current is ",IE," mA."
#Correction about conversion of micro-Ampere and milli-Ampere to be done in the book.
```

In [13]:

```
import math
#Variables
ICBO = 10 * 10**-3 #Leakage current (in milli-Ampere)
beta = hFE = 50 #common emitter current gain
T2 = 50.0 #Temperature (in degree Celsius)
T1 = 27.0 #Temperature (in degree Celsius)
#Calculation
#Case (a)
IB = 0.25 #Base current (in milli-Ampere)
IC = beta * IB + (1 + beta)* ICBO #Value of new collector current (in milli-Ampere)
#Case (b)
ICBO1 = ICBO * 2**((T2 - T1)/10) #ICBO at 50 degree celsius (in milli-Ampere)
IC1 = beta * IB + (1 + beta)* ICBO1 #Value of new collector current (in milli-Ampere)
#Result
print "Collector current when IB = 0.25 mA is ",IC," mA.\nCollector current at 50 degree Celsius is ",round(IC1,2)," mA."
```