Worked example: A 12 V battery connects to R1 = 4 Ω and R2 = 6 Ω (a) in series, (b) in parallel. Find total current, and the voltage and power for each resistor. Step 1 (series): Req = 10 Ω, I = 12/10 = 1.2 A (same through both). V1 = 1.2 × 4 = 4.8 V, V2 = 1.2 × 6 = 7.2 V (sum 12 ✓). P1 = I²R1 = 5.76 W, P2 = 8.64 W — the bigger resistor takes more power. Step 2 (parallel): Req = (4×6)/10 = 2.4 Ω, I_total = 12/2.4 = 5 A. Each sees 12 V: I1 = 3 A, I2 = 2 A (sum 5 ✓). P1 = V²/R1 = 36 W, P2 = 24 W — now the smaller resistor takes more power. Step 3: Compare — parallel draws far more total power (60 W vs 14.4 W) because each resistor gets the full voltage.