Question 1: Define a microcontroller and explain its role in a programmable system.

Answer: A microcontroller is a compact integrated circuit that contains a processor, memory, and input/output interfaces. Its role is to control and coordinate the operation of electronic devices based on programmed instructions.

Question 2: Describe the main difference between a simple switch and a relay in an electronic system.

Answer: A simple switch manually opens or closes a circuit to turn devices on or off, while a relay is an electrically operated switch that uses a small control signal to switch a larger current on or off.

Question 3: A student wants to design a system that turns on a lamp when it gets dark. Which programmable component would be suitable for this project? Explain why.

Answer: A light-dependent resistor (LDR) with a microcontroller would be suitable because it can detect changes in light levels and trigger the lamp to turn on when darkness is detected.

Question 4: Sketch a simple circuit diagram showing how a microcontroller can be connected to an LED and a push-button switch. Label all components clearly.

Answer: A correct sketch would show a microcontroller with a digital input pin connected to a push-button switch (with a pull-down resistor), and an output pin connected to an LED (with a current-limiting resistor).

Question 5: Explain how a programmable timer can be used in an automated watering system.

Answer: A programmable timer can be set to activate a water pump at specific times, ensuring the plants are watered regularly without manual intervention.

Question 6: Identify two safety considerations when working with programmable electronic components.

Answer: Ensure circuits are powered off before making adjustments, and avoid exposing components to water or moisture to prevent short circuits and electric shocks.

Question 7: [WORKING WITH CODE] Describe the purpose of a 'loop' in programming a microcontroller for a sensor-based system.

Answer: A loop allows the microcontroller to continuously check sensor inputs and respond accordingly, enabling real-time operation of the system.

Question 8: Sketch a flowchart illustrating the basic logic for a system that turns on a fan when a temperature sensor detects a high temperature. Include decision points and actions.

Answer: A correct flowchart would start with reading the temperature sensor, then a decision point: 'Is temperature high?'. If yes, turn on the fan; if no, keep it off. Loop back to repeated monitoring.

Question 9: Design a brief plan for a project that uses a programmable component to control a door lock. Include what components you would need and the basic operation.

Answer: Components: microcontroller, keypad or RFID reader, electronic lock, power supply. The system allows users to input a code or scan an RFID card to unlock the door, with the microcontroller processing input and controlling the lock.

Question 10: [EVALUATION] List two advantages of using programmable components in modern systems.

Answer: They allow automation and customization of functions, and enable systems to be easily updated or modified through programming instead of hardware changes.