England · WJEC EduqasQ&A
ElectronicsQ&A by dot point
A short Q&A bank for every England Electronics syllabus dot point. Each question and answer is drawn directly from our worked dot-point page, so you can scan key concepts before opening the long-form answer.
Component 2 Application of Electronics
- The 555 astable: producing a continuous square-wave output, the frequency and period equations, the duty cycle, and using an astable as a clock or flasher.3Q&A pairs
- The 555 monostable: producing a single output pulse when triggered, the pulse-duration equation, and using a monostable for timed delays and switch debouncing.3Q&A pairs
- Operational amplifiers: the op-amp as a high-gain amplifier, negative feedback, and the inverting and non-inverting amplifier gains.3Q&A pairs
- Power supplies: rectifying a.c. to d.c., smoothing with a reservoir capacitor, the idea of ripple, and stabilising the output voltage.3Q&A pairs
Component 1 Discovering Electronics
- Binary numbers and adders: counting in binary, the half adder (sum and carry), the full adder with a carry in, and adding multi-bit numbers.3Q&A pairs
- Boolean algebra: writing Boolean expressions for gates, the laws of Boolean algebra, De Morgan's laws, and simplifying an expression to use fewer gates.3Q&A pairs
- Designing combinational logic: building a circuit from a truth table or word description, combining gates, and the universal NAND and NOR gates.3Q&A pairs
- Logic gates: AND, OR, NOT, NAND, NOR and XOR, their symbols and truth tables, and the digital high and low logic levels.3Q&A pairs
Component 1 Discovering Electronics
- Circuit concepts: charge, current, voltage (potential difference) and resistance, their units, and Ohm's law relating voltage, current and resistance.3Q&A pairs
- Measuring and testing circuits: connecting voltmeters, ammeters and multimeters, the difference between measuring across and through, and reading circuit and timing signals on an oscilloscope.4Q&A pairs
- Electrical power and energy: power as the rate of energy transfer, the equations relating power to voltage, current and resistance, and resistor power ratings.3Q&A pairs
- Series and parallel circuits: the rules for current and voltage in each, and combining resistors in series and in parallel.5Q&A pairs
- Electronic systems and subsystems: the systems approach with input, process and output blocks, block diagrams and signal flow, and analogue versus digital signals.4Q&A pairs
Component 1 Discovering Electronics
- Capacitors and time delays: charge stored on a capacitor, the RC time constant, and how a charging capacitor in a potential divider produces a time delay.3Q&A pairs
- Driving LEDs: the need for a current-limiting series resistor, the forward voltage drop of an LED, and calculating the resistor value for a chosen current.3Q&A pairs
- Fixed and variable resistors: preferred (E-series) values, the resistor colour code, tolerance, and variable resistors (potentiometers and rheostats).4Q&A pairs
- Potential dividers: the potential-divider equation, choosing resistor values for a target output voltage, and the effect of loading the output.3Q&A pairs
- Sensing subsystems: light-dependent resistors and thermistors, their resistance behaviour, and building light and temperature sensing circuits with potential dividers.3Q&A pairs
Component 2 Application of Electronics
- Counters: chaining flip-flops to count clock pulses in binary, frequency division by each stage, and the modulus of a counter.3Q&A pairs
- Flip-flops and latches: storing one bit, the difference between sequential and combinational logic, the D-type flip-flop, and edge triggering by a clock.3Q&A pairs
- Interfacing and system design: matching analogue and digital subsystems, signal conditioning between stages, and designing and testing a complete input-process-output system.3Q&A pairs
- Microcontrollers: the microcontroller as a programmable processing subsystem, inputs and outputs, and planning a control program with a flowchart.3Q&A pairs
- Seven-segment displays and decoders: the seven-segment display, the decoder that drives it from a binary count, and common-anode and common-cathode types with current-limiting resistors.3Q&A pairs
Component 1 Discovering Electronics
- Diodes: forward and reverse bias, the forward voltage drop, the LED, rectification, and protecting circuits against reverse current and back-EMF.3Q&A pairs
- Latching switches and feedback: using a relay or positive feedback to latch an output on, the need for a reset, and how feedback gives a snap (Schmitt) action that avoids chatter.3Q&A pairs
- MOSFET switching: the MOSFET as a voltage-controlled switch, the gate threshold voltage, why it draws no steady gate current, and choosing between a MOSFET and a bipolar transistor.3Q&A pairs
- Transistor switching: the bipolar transistor as a switch, cut-off and saturation, current gain, and choosing the base resistor to drive a load.3Q&A pairs
- Comparators: comparing two voltages, the reference set by a potential divider, the digital output, and using a comparator to make a sensing system switch at a threshold.3Q&A pairs