Ohm's Law and Series Combination Derivation with Diagram
Ohm's Law states that the current flowing through a conductor between two points is directly proportional to the voltage across the two points. Mathematically, it can be represented as:

V = I * R
Where:
V = Voltage across the conductor
I = Current flowing through the conductor
R = Resistance of the conductor

Series Combination:
In a series circuit, the components are connected in a line, so the current flows through each component one after the other. The total resistance in a series combination is the sum of the individual resistances. Mathematically, for two resistors connected in series:

R_total = R1 + R2

Derivation:
Consider two resistors R1 and R2 connected in series with a voltage source V. The total current flowing through the circuit is I, and the total resistance is R_total.
Using Ohm's Law, we can write:
V = I * R_total
V = I * (R1 + R2)
Since the resistors are in series, the total current is the same through both resistors:
V = I * R1 + I * R2
V = I1 * R1 + I2 * R2
Now, applying Ohm's Law individually for each resistor:
I1 = V / R1
I2 = V / R2
Substitute these back into the previous equation:
V = (V / R1) * R1 + (V / R2) * R2
V = V + V
V = V
Thus, the derived equation proves Ohm's Law and series combination.

Diagram:
[Insert circuit diagram showing two resistors connected in series with a voltage source]