Question

Use Ohm’s law to determine the potential difference across the 3 \(\Omega\) resistor in the circuit shown in the following diagram when key is closed:

Answer 1

Step 1: Understand the arrangement
We are given three resistors of values 1 Ω, 2 Ω, and 3 Ω connected in series with a battery of voltage 2 V.

Step 2: Calculate total resistance
In a series circuit, the total resistance is the sum of all individual resistances:
R_total = 1 Ω + 2 Ω + 3 Ω = 6 Ω

Step 3: Use Ohm’s law to calculate the current
Ohm’s law is given by: I = V / R
Here, V = 2 V and R_total = 6 Ω
So, I = 2 / 6 = 0.333 A

Step 4: Find the potential difference across the 3 Ω resistor
To calculate voltage across a resistor in series: V = I × R
Here, I = 0.333 A and R = 3 Ω
V = 0.333 × 3 = 1 V

Step 5: Final Answer
The potential difference across the 3 Ω resistor is 1 V.