In [1]:

```
import math
#Variables
IT = 20 #Total current (in milli-Ampere)
I2 = 4 #Current (in milli-Ampere)
#Calculation
I1 = IT - I2 #Current (in milli-Ampere)
#Result
print "Value of the current I1 is ",I1," mA."
```

In [3]:

```
import math
#Variables
I = 1 #Current (in Ampere)
#Calculation
#Applying Kirchoff's voltage law:
#(1 *3) + (1 * R) + (1 * 4) - 12 =0
R = 5 #Resistance (in ohm)
#Result
print "Value of R is ",R," ohm."
```

In [6]:

```
import math
#Variables
Vs = 100 #Source Voltage (in volts)
I = 5 #Current entering the circuit (in Ampere)
IL = 5 #Current leaving the circuit (in Ampere)
R15 = 15 #Resistor of 15 ohm (in ohm)
V15 = 30 #Voltage across 15 ohm resistor (in ohm)
#Calculation
I1 = V15 / R15 #Current through 15 ohm resistor (in Ampere)
IA = I + I1 #Current entering junction A (in Ampere)
#Applying Kirchoff's current law
I2 = I + I1 #Current through 5 ohm resistor (in Ampere)
IB = I2 #Current entering juction B (in Ampere)
IR = IA - IL #Current through R (in Ampere)
#Applying Kirchoff's voltage law
#(7 * 5) + (2 *R) - 100 + 30 =0
R = 35.0/2
#Result
print "The value of R is ",R," ohm."
```

In [36]:

```
import math
#Variables
V = 25 #Source voltage (in volts)
RB = 99 #Resistance (in kilo-ohm)
RC = 2 #Resistance (in kilo-ohm)
RE = 1 #Resistance (in kilo-ohm)
VCE = 5 #Voltage across C and E (in volts)
#Calculation
#Applying Kirchoff's Voltage law:
#IB*RB + VBE + IE*RE -V = 0
#IB*RB + VBE + (IB + IC)*RE - VCC = 0
#100*IB + IC = 24
#IB + 3*IC = 20
IC = 1976.0/299
IB = 20 - (3 * 6.61)
#Result
print "Value of IB is ",round(IB,3)," mA.\nValue of IC is ",round(IC,3)," mA."
```

In [56]:

```
import math
#Variables
VS1 = 5 #Voltage source 1 (in volts)
VS2 = 3 #Voltage source 2 (in volts)
V6 = 0 #Voltage drop across 6 ohm resistor when AB is open (in volts)
R1 = 6 #Resistor (in ohm)
R2 = 4 #Resistor (in ohm)
#Calculation
I = 5.0/4 #Current through 4 ohm resistor (in Ampere)
V = I * R2 #Voltage drop across 4 ohm Resistor (in volts)
VOC = VS2 + V6 + V #Open circuit voltage (in volts)
Rth = R1
#Result
print "Thevenin's equivalent Voltage is ",VOC," V.\nThevenin's equivalent resistance is ",Rth," ohm."
```

In [59]:

```
import math
#Variables
V = 25.0 #Source voltage (in volts)
R1 = 100.0 #Resistance (in ohm)
R2 = 75.0 #Resistance (in ohm)
R3 = 50.0 #Resistance (in ohm)
R4 = 25.0 #Resistance (in ohm)
RL = 250.0 #Load resistance (in ohm)
#Calculation
I = V / (R1 + R2 + R3) #Series curren (in Ampere)
VR2 = I * R2 #Voltage drop across R2
VOC = VR2 #Open circuit voltage (in volts)
Vth = VOC #Thevenin's equivalent voltage (in volts)
Rth = R4 + R2*(R1 + R3)/(R1 + R2 + R3) #Thevenin's equivalent resistance (in ohm)
IL = Vth/(Rth + RL)
#Result
print "Thevenin's equivalent voltage is ",round(Vth,3)," V. and resistance in ",Rth," ohm."
print "Current through load resistance is ",round(IL,3)," A."
```

In [2]:

```
import math
#Variables
R1 = 2.0 #Resistance (in kilo-ohm)
R2 = 1.0 #Resistance (in kilo-ohm)
R3 = 2.0 #Resistance (in kilo-ohm)
I = 0.1 #Current source (in Ampere)
#Calculation
#Using Thevenin's theorem :
I2 = I * R1 / (R1 + (R2 +R3)) #Current through brach ECD (in Ampere)
VR3 = I2 * R3* 10 **3 #Voltage drop across R3 (in volts)
Vth = VR3 #Thevenin's Voltage
Rth = R3 * (R1 + R2)/(R1 + R2 + R3)
#Result
print "Thevenin's voltage is ",Vth," V.\nThevenin's Resistance is ",Rth," kilo-ohm."
```

In [4]:

```
import math
#Variables
R1 = 0.6 #Resistance (in ohm)
R2 = 0.6 #Resistance (in ohm)
R3 = 0.8 #Resistance (in ohm)
R4 = 0.8 #Resistance (in ohm)
#Calculation
Rth = R3 + R4*(R1 + R2)/(R4 + (R1 +R2)) #Thevenin's resistance (in ohm)
#Result
print "The value of Rth is ",Rth," ohm."
```

In [6]:

```
import math
#Variables
V = 12.0 #Voltage (in volts)
R1 = 3.0 #Resistance (in ohm)
R2 = 9.0 #Resistance (in ohm)
#Calculation
#Using Norton's Theorem
Isc = V / R1 #Short circuit current (in Ampere)
IN = Isc #Norton's Current (in Ampere)
RN = R1 * R2 / (R1 + R2) #Norton's resistance (in ohm)
#Result
print "Norton's Current is ",IN," A.\nNorton's Resistance is ",RN," ohm."
```

In [9]:

```
import math
#Variables
V = 15.0 #Voltage 15 volt battery (in volts)
R1 = 6.0 #Resistance (in ohm)
R2 = 3.0 #Resistance (in ohm)
R3 = 3.0 #Resistance (in ohm)
V0 = 30.0 #Voltage 30 volt battery (in volts)
#Calculation
R4 = R2 * R3 / (R2 + R3) #R4 = R2 || R3 (in ohm)
V1 = R4 / (R1 + R4) * V #Voltage drop across R4 (in volts)
R5 = R1 * R3 / (R1 + R3) #R5 = R1 || R3 (in ohm)
V2 = R5 / (R2 + R5) * V0 #Voltage drop across R5 (in volts)
I = V/R3
#Result
print "In case 1: Voltage drop across R3 is ",V1," V.\nIn case 2: Voltage drop across R3 is ",V2," V.\nThe current through R3 is ",I," A."
```

In [13]:

```
import math
#Variables
Vth = 100 #Thevenin Voltage (in micro-volts)
Rth = 50 #Thevenin Resistance (in ohm)
#Calculation
RL = Rth #Maximum Load Resistance (in ohm)
PL = (Vth/(Rth + RL))**2 *RL #Maximum load power (in pico-watt)
#Result
print "Maximum load resistance is ",RL," ohm.\nMaximum load power is ",PL," pW."
```

In [1]:

```
import math
#Variables
VTH = 20.0 * 10**-3 #Thevenin's Voltage (in volts)
RTH = 300.0 #Thevenin's Resistance (in ohm)
RL = 300.0 #Load Resistance (in ohm)
#Calculation
PL = (VTH/(RTH + RL))**2 * RL #Power across load resistance (in watt)
#Result
print "The value of power transmitted to the receiver is ",round(PL*10**6,2)," micro-watt."
```

In [62]:

```
import math
#Variables
R1 = 5.0 #resistance (in ohm)
R2 = 2.0 #resistance (in ohm)
R3 = 3.0 #resistance (in ohm)
#Calculation
Req = R2 * R3 / (R2 + R3) #Equivalent resistance (in ohm)
RL = R1 + Req
#Result
print "Load resistance is ",RL," ohm."
```