Series vs parallel resistors

// WHAT YOU WILL LEARN

Series: R1 + R2 (2 × 1 kΩ = 2000 Ω). Parallel: (R1 × R2) ÷ (R1 + R2) = 500 Ω — same parts, 4× the current.

// LESSON NOTES

Same 2 resistors… 4× the current? 🤯

SERIES (one path): R = R1 + R2
1000 + 1000 = 2000 Ω → 5 V ÷ 2000 Ω = 2.5 mA

PARALLEL (two paths): R = (R1 × R2) ÷ (R1 + R2)
(1000 × 1000) ÷ 2000 = 500 Ω → 5 V ÷ 500 Ω = 10 mA

Rule: series makes R bigger than the biggest. Parallel makes it smaller than the smallest.

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