Answer: Step-up transformer.
- A Step-down transformer
- B Rectifier
- C Step-up transformer
- D Inductor
Correct answer: C. Step-up transformer
Explanation: Step-up transformer: more secondary turns than primary. Vs/Vp = Ns/Np > 1, so secondary voltage is higher.
In a pure inductor the current lags the voltage by 90° (energy is briefly stored in the magnetic field before current responds); in a pure capacitor the current leads the voltage by 90° (current must flow to build up charge before voltage rises) - the mnemonic "ELI the ICE man" keeps these straight.
Concept context
AC circuits, impedance, LCR series circuit, resonance, transformers, and power factor.