Question

Explain the concept of voltage division in a circuit using Ohm's Law.

Answer 1

Voltage division is a fundamental concept in electrical circuits that describes how the voltage across multiple resistors connected in series can be distributed or divided among them. Ohm's Law, which states that the current (I) flowing through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance (R) of the conductor, is a key principle in understanding voltage division.

Ohm's Law is expressed by the formula:

V = I * R

Where:
V = Voltage (in volts)
I = Current (in amperes)
R = Resistance (in ohms)

Now, let's consider a simple circuit with two resistors (R1 and R2) connected in series, meaning the current flows through one resistor and then through the other. The total voltage across the two resistors is V_total, and the individual voltages across R1 and R2 are V1 and V2, respectively.

According to Ohm's Law, the current (I) is the same through both resistors since they are in series. Thus, we can express the current as:

I = V_total / (R1 + R2)

Now, let's calculate the individual voltages across R1 and R2 using Ohm's Law:

V1 = I * R1
V2 = I * R2

Substituting the value of I from the first equation:

V1 = (V_total / (R1 + R2)) * R1
V2 = (V_total / (R1 + R2)) * R2

The above equations show how the voltage across each resistor is directly proportional to its resistance. The larger the resistance of a resistor, the larger its voltage drop will be, and vice versa.

In summary, voltage division using Ohm's Law explains how the total voltage across resistors in series is divided proportionally based on their respective resistances. This concept is crucial for understanding and designing various electronic circuits, as it helps determine the voltage at different points and enables us to choose appropriate resistors to achieve the desired voltage distribution.