🔍 Key Concepts

• Commutator vs. slip rings and what type of generator each one is used on (AC or DC). • How a single‑loop generator looks in textbooks when illustrating basic AC versus basic DC generation. • Whether the field poles (N and S) change polarity anywhere between figures A, B, C, and D.

💭 Think About

• Look closely at the rotating element: are there solid rings or a split ring, and what does that tell you about whether the output is AC or DC? • Trace the current path from the rotating coil, through the commutator/brushes, to the load: does the external circuit see current that reverses direction or stays in one direction as the loop turns? • Examine the N and S pole pieces in all four sketches: do they ever swap or is something else changing instead?

✅ Before You Answer

• Confirm whether a split-ring commutator is drawn (two segments with a brush) or continuous rings. • Verify if the external load terminals are marked with a steady + / − or if their polarity is changing with rotation. • Check that the field poles (N and S) remain fixed in all four positions; ask yourself if that allows the field polarity to reverse.