Series Circuits
In a series circuit, components are connected end-to-end in a single path for current to flow. The same current flows through each component.
Key Characteristics:
- Current (I): Same through all components
- Voltage (V): Divided across components
- Total Resistance (Rtotal): Sum of all resistances
Rtotal = R₁ + R₂ + R₃ + ...
Example 1: Finding Total Resistance
Three resistors (5 Ω, 10 Ω, 15 Ω) are connected in series. What is the total resistance?
Formula: Rtotal = R₁ + R₂ + R₃
Calculation: Rtotal = 5 + 10 + 15 = 30 Ω
Answer: The total resistance is 30 ohms.
Example 2: Finding Voltage Drop
A 12 V battery is connected to two resistors in series: 4 Ω and 8 Ω. What is the voltage drop across each?
Total Resistance: Rtotal = 4 + 8 = 12 Ω
Current: I = V / R = 12 V / 12 Ω = 1 A
Voltage drop across 4 Ω: V = I × R = 1 A × 4 Ω = 4 V
Voltage drop across 8 Ω: V = 1 A × 8 Ω = 8 V
Check: 4 V + 8 V = 12 V (matches source)