Determining signal amplitude and frequency from CRO measurements

Steps:

• Measure peak-to-peak amplitude: waveform spans 2 vertical divisions, so amplitude = 2 × 5 mV/division = 10 mV.
• Measure period: one complete cycle spans 4 horizontal divisions, so T = 4 × 5 ms/division = 20 ms.
• Calculate frequency: f = 1/T = 1/0.020 s = 50 Hz.
• Combine results: amplitude 10 mV, frequency 50 Hz.

Why A is correct:

• Matches exact calculations: amplitude from Y-gain scaling and period from time-base, per CRO measurement principles.

Why the others are wrong:

• B: Option incomplete or invalid, no matching values.
• C: Amplitude overstated (20 mV assumes 4 divisions, but diagram shows 2).
• D: Amplitude overstated and frequency doubled (100 Hz assumes T=10 ms or 2 divisions, but diagram shows 4).

Final answer: A