Singapore · SEABQ&A
ElectronicsQ&A by dot point
A short Q&A bank for every Singapore 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.
Amplifiers and Operational Amplifiers
- Apply the gain equations for the inverting and non-inverting op-amp amplifier and explain the role of negative feedback3Q&A pairs
- Explain the operational amplifier used as a comparator, including its very high gain and the two output states1Q&A pairs
- Explain how a single transistor amplifies a small signal, the need for biasing, and the meaning of voltage amplification3Q&A pairs
- Define voltage gain as a ratio, calculate it, and express it in decibels using the gain equation2Q&A pairs
Analogue Electronics
- Describe an analogue signal, read a waveform on an oscilloscope, and calculate amplitude, period and frequency2Q&A pairs
- Explain how a capacitor charging through a resistor produces a time delay and how the delay depends on resistance and capacitance1Q&A pairs
- Apply the potential divider equation to find an output voltage and explain how a sensor in a divider produces a varying voltage2Q&A pairs
- Explain a sensor-driven transistor switching circuit and design one to turn a load on in the dark or when it is hot1Q&A pairs
Basic Circuit Concepts
- Recognise and draw standard circuit symbols, interpret a circuit diagram, and use the conventions for current direction and meter connection4Q&A pairs
- Define current, voltage (potential difference) and resistance, state their units, and explain how they relate in a simple circuit4Q&A pairs
- Define electrical power and energy, apply the power equations, and calculate energy transferred and the cost of running a device4Q&A pairs
- State and apply Ohm's law, define resistance from it, and recognise ohmic and non-ohmic components from their V-I graphs5Q&A pairs
- Apply the rules for current, voltage and resistance in series and parallel circuits, and calculate combined resistance3Q&A pairs
Digital Electronics and Logic Gates
- State the function, symbol, truth table and Boolean expression of the AND, OR and NOT logic gates1Q&A pairs
- Describe digital logic levels, explain binary representation, and convert between small binary and denary numbers2Q&A pairs
- Design a simple logic system from a written specification by building its truth table and selecting the gates needed2Q&A pairs
- State the function, truth table and Boolean expression of the NAND and NOR gates and explain why NAND is universal3Q&A pairs
- Derive the truth table of a combinational logic circuit built from two or more gates and write its Boolean expression3Q&A pairs
Electronic Components
- Describe a capacitor as a charge-storing component, define capacitance, and apply the relationship between charge, capacitance and voltage2Q&A pairs
- Describe the diode as a one-way component, state its forward voltage, and explain half-wave rectification of an alternating supply3Q&A pairs
- Describe the LED as a light-emitting one-way component and calculate the series resistor needed to set a safe LED current1Q&A pairs
- Describe the function and types of resistor, read the four-band resistor colour code, and choose a resistor value1Q&A pairs
- Describe the bipolar transistor, name its three terminals, and explain how a small base current controls a larger collector current4Q&A pairs
Practical Construction and Testing
- Describe building circuits on breadboard and stripboard, explain their internal connections, and state safe soldering practice2Q&A pairs
- Apply a systematic fault-finding method to a circuit, identify common faults, and test a circuit against its specification3Q&A pairs
- Use a multimeter to measure voltage, current and resistance, connecting it correctly and choosing a suitable range4Q&A pairs
Sensors and Transducers
- Describe the LDR and the thermistor as input transducers, state how their resistance changes, and use them in a potential divider3Q&A pairs
- Describe common output transducers (lamp, LED, buzzer, motor, loudspeaker) and the energy conversion each one performs1Q&A pairs
- Describe switches and variable resistors as input devices and explain how a switch with a pull-down resistor gives a logic input4Q&A pairs
- Explain how a relay lets a small current switch a large or isolated load and why a flyback diode is connected across the coil0Q&A pairs
Systems and Signal Processing
- Compare analogue and digital signals, state the advantages of digital, and describe converting between the two3Q&A pairs
- Explain feedback in a control system, distinguish negative from positive feedback, and describe a closed-loop control example2Q&A pairs
- Describe the input-process-output systems model and use block diagrams to represent an electronic system3Q&A pairs