Units, prefixes and standard form
Convert prefixes, squared and cubed units. Write numbers in standard form.
Read voltage amplitude, peak-to-peak voltage, period, frequency and phase difference.
Find the time period in s of trace A. Give your answer to 3 significant figures.
Ideal sinusoidal voltage traces; one large square is one division. A is solid and B, when present, is dashed. Both channels have the same sensitivity and time-base.
Trace A has amplitude 1 divisions and period 5 divisions. Vertical sensitivity 0.5 V/div; time-base 1 ms/div.
Treat the given values as exact unless an uncertainty is stated.
Measure one complete cycle, multiply by ms/div, then convert milliseconds to seconds. For frequency, use f = 1/T.
Multiply vertical divisions by volts per division. Amplitude runs from the zero line to a peak; peak-to-peak spans both extremes. Multiply horizontal divisions for one complete cycle by the time-base. Convert ms to s before using f = 1/T.
For traces of the same frequency, use corresponding rising zero crossings or matching peaks. Phase magnitude = horizontal shift / period span × 360°. The dashed trace B is shifted right and lags A here. A half-cycle shift is 180°; at that limit leading and lagging are equivalent descriptions.
These are ideal sinusoidal signals with a shared sensitivity and time-base. Triggering, probe attenuation, offsets, noise and rms voltage are outside these tasks.
AQA 7408: 7.1 AT h (selected); AQA 7408: 3.3.1.1 (selected); OCR A H556: 1.2.2(h); 4.4.1(b–c) (selected). Tasks cover the selected skills listed above.
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