WJEC A Level Physics
WJEC A Level Physics Option A: Alternating Currents Exam Questions
Free WJEC A Level Physics exam questions on Option A: Alternating Currents, with mark schemes. Covers ac waveforms, rms values, the oscilloscope and rectification.
Option A: Alternating Currents exam questions
1 question pack of real past exam questions with its mark scheme. Answer every question without notes, then mark your answers line by line against the mark scheme.
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A Level Physics Flashcards
Every answer is written in mark scheme wording, so you learn exactly what examiners give marks for. Pick your exam board, then test yourself with the questions on this page.
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About WJEC A Level Physics Option A: Alternating Currents
This topic covers alternating supplies.
What you need to know
- Waveforms Peak, peak-to-peak, period and frequency.
- rms Vrms = V₀/√2.
- Oscilloscope Using time base and y-gain to measure values.
- Mean power P = Irms Vrms.
Common mistakes in Option A: Alternating Currents
- Using peak values for power.
- Reading oscilloscope divisions wrongly.
- Confusing period and frequency.
Try three Option A: Alternating Currents exam-style questions
1. Find the peak voltage of a 230 V rms supply. (1 mark)
Show the mark scheme answer
325 V.
2. Explain why rms values are used. (1 mark)
Show the mark scheme answer
They give the same power as an equivalent dc value.
3. A trace has period 4 divisions at 5 ms per division. Find f. (1 mark)
Show the mark scheme answer
50 Hz.
Option A: Alternating Currents FAQs
What does Alternating Currents cover?
ac waveforms, rms values and oscilloscopes.
Is mains peak or rms?
UK mains 230 V is rms.
What is the mean value of a sine wave over a cycle?
Zero.
Revise this topic with flashcards: A Level Physics Flashcards, with mark scheme answers for Anki and Quizlet.
