Advanced Qualification · A-003 Measurements · A-003-001-004
If the peak value of a 100 Hz sinusoidal waveform is 20 volts, the RMS value is:
- A16.38 volts
- B14.14 volts
- C28.28 volts
- D7.07 volts
Correct answer: B — 14.14 volts. From the official ISED question bank, verified word for word.
Why
For a smooth sine wave like this 100 Hz signal, the root mean square, or RMS, value represents the equivalent steady voltage that would deliver the same power to a heater. The full explanation — and one for every question — is in Pro.
Practise this section
Measurements is section A-003 of the Advanced exam: Measurements: meters, oscilloscopes, counters, signal generators, and what a reading actually tells you.
Drill A-003 — free, no account