Draw a schematic diagram of a circuit consisting of a battery of three cells of 2 V each, a 5 Ω resistor, an 8 Ω resistor, and a 12 Ω resistor, and a plug key, all connected in series.
Hint. Every component sits on a single loop, one after another, with no branching.
Step 1 — Combine the cells. Three 2 V cells in series give a battery of 6 V total, drawn as several cell symbols in a row with consistent polarity.
Step 2 — Arrange the rest of the loop. The battery, the 5 Ω, 8 Ω and 12 Ω resistors, and the plug key are all connected one after another in a single unbranched loop, since that's what 'all connected in series' requires.
✦ Answer: A single closed loop containing the 6 V battery (three 2 V cells), the 5 Ω, 8 Ω and 12 Ω resistors, and the plug key, all in one path with no branches.
Where students slip. Drawing the resistors on separate branches — a series connection specifically means one single path, with every component carrying the same current.
