Series & Parallel Circuits Worksheet
Goal: Compare series and parallel connections of two resistors: the equivalent resistance, the total current and how the current divides between the branches.
What to do
- Press Reset (12 V, R₁ = 100 Ω, R₂ = 200 Ω, Series). Record the equivalent resistance and the three currents.
- Switch to Parallel and record the same readings.
- Press Reset, then “Equal resistors”. Record a Series row and a Parallel row. Do the same with “Unequal resistors”.
Record your results
| Setting | Equivalent R | Total current | Current R₁ | Current R₂ |
|---|---|---|---|---|
| 100 Ω and 200 Ω, series | ||||
| 100 Ω and 200 Ω, parallel | ||||
| Equal (100 Ω, 100 Ω), series | ||||
| Equal (100 Ω, 100 Ω), parallel | ||||
| Unequal (50 Ω, 200 Ω), series | ||||
| Unequal (50 Ω, 200 Ω), parallel |
Questions
In series, the current through R₁ and R₂ was always the same. Why?
How do you find the equivalent resistance in series and in parallel? Check your rules with the 100 Ω and 200 Ω rows.
Why does the parallel circuit draw more total current from the same 12 V supply?
In parallel with 100 Ω and 200 Ω, which branch carries more current? How do the branch currents add up?
Two equal 100 Ω resistors in parallel give what equivalent resistance? Explain the pattern.
Challenge: in the unequal series circuit (50 Ω and 200 Ω), what is the voltage across each resistor? Use V = IR.
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