Question 1: Describe how a microcontroller can be used to control a simple automatic lighting system in a classroom. Include the main components involved.

Answer: A microcontroller receives input from a light sensor (photocell). When the light level drops below a set threshold, the microcontroller sends a signal to turn on the lighting system. Components include the microcontroller, light sensor, power supply, and relay or transistor for switching the lights.

Question 2: Sketch a basic circuit diagram for a system that uses a programmable component to turn on a fan when a temperature sensor detects heat. Label all major components.

Answer: A sketch showing a temperature sensor connected to a microcontroller, with the microcontroller connected to a relay that switches the fan on. Labels should include the temperature sensor, microcontroller, relay, power supply, and the fan.

Question 3: Explain the function of an input device and an output device in a programmable electronic system.

Answer: An input device detects or receives signals from the environment, such as sensors or switches. An output device responds to the microcontroller's signals by performing an action, such as turning on a light or activating a motor.

Question 4: [WORKING WITH PROGRAMMABLE COMPONENTS] List three common types of microcontrollers used in student projects and give one example of a project for each.

Answer: 1. Arduino Uno - Used for controlling LED displays. 2. Raspberry Pi - Used for media projects and web servers. 3. Micro:bit - Used for simple coding projects like step counters.

Question 5: Design a simple control system that uses a programmable component to open a door when a correct code is entered. Describe the process and key components involved.

Answer: The system includes a keypad input connected to a microcontroller. When the correct code is entered, the microcontroller activates a servo motor to unlock the door. Components include keypad, microcontroller, servo motor, power supply, and possibly an LCD display for instructions.

Question 6: Sketch a flowchart showing the basic operation of a programmable system that turns on a water pump when a moisture sensor detects dry soil. Include decision points and actions.

Answer: A flowchart with start, reading moisture sensor data, a decision point (is soil dry?), if yes, turn on pump; if no, do nothing or turn off pump. End with a loop back to sensor reading.

Question 7: Identify and explain two safety considerations when designing systems with programmable electronic components.

Answer: 1. Ensure proper insulation and grounding to prevent electric shocks. 2. Include current limiting devices such as resistors or fuses to prevent overheating or damage to components.

Question 8: [DESIGN BRIEF] You need to develop a programmable alarm system that activates when a window is opened. Describe your plan including the components you would use and how the system works.

Answer: Use a magnetic reed switch as an input sensor attached to the window. When the window opens, the switch closes or opens the circuit, sending a signal to a microcontroller. The microcontroller then activates a buzzer or siren as the alarm. Components include reed switch, microcontroller, buzzer, power supply, and wiring.

Question 9: Explain the difference between a program running on a microcontroller and one running on a computer.

Answer: A program on a microcontroller is typically embedded, small, and designed for specific tasks with limited resources, while a computer program can be larger, more complex, and run on a general-purpose operating system.

Question 10: [EVALUATION] Suggest two improvements to a programmable traffic light system to make it more efficient or safer.

Answer: 1. Incorporate sensors to detect traffic flow and adjust timings dynamically. 2. Add pedestrian crossing buttons with automatic detection of pedestrians waiting to improve safety.