Physics 7408/3BE June 2018

The AQA Paper 3 Physics exam (June 2018), Section B (Electronics), includes a variety of questions on logic circuits, amplifiers, and communication systems. It starts with Boolean expressions and truth tables for logic gates, then compares two logic circuits that produce the same output. The paper also explores the operation of ultrasound sensors and amplifiers, including calculations related to voltage gain and resistor selection. Further, it covers the design and function of an amplitude modulation (AM) signal in radio communication, and examines the design of timing circuits such as astable multivibrators, including calculations for resistors and capacitors. Finally, the section discusses analogue-to-digital conversion in the context of recording studio equipment, focusing on quantization and factors affecting the quality of digital signals.