Electronics
Overview
Electronics gives a designer a way to make products sense their surroundings, make simple decisions, and respond - switching on a light when it gets dark, sounding an alarm when a door opens, or holding a motor at a steady speed. Underneath every smart product is the same idea: an input is detected, a process decides what to do, and an output makes something happen. Learn to read that pattern and you can analyse almost any electronic circuit you meet.
This note covers the 0445 electronics objectives: drawing circuits with correct symbols and conventions; the common input, process and output components from power sources and switches through sensors and transistors to lamps, buzzers and motors; the difference between open and closed loop systems and the role of feedback; what programmable integrated circuits add to a design; and how to build and test circuits safely using both real components and virtual modelling. Concrete calculations, including a full potential-divider design, are worked through so you can apply the theory.
Objectives
- use correct symbols and conventions when drawing circuit diagrams
- show knowledge of common input, process and output components, including: - power sources - switches - movement components - light-emitting components - sound-emitting components - sensing components - transistors
- identify and show knowledge of open and closed loop systems - input, process, output and feedback
- understand the use of programmable integrated circuits
- show knowledge of building and testing of simple circuits through physical and/or virtual modelling.
Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Electronics. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- On a circuit diagram, what does a solid dot at the meeting point of two wires indicate? A. The wires cross but are not connected B. The wires are electrically joined at that point C. A resistor is present D. The current stops at that point Answer: B
- Which component's resistance decreases as the light falling on it increases? A. Thermistor B. Light-dependent resistor (LDR) C. Variable capacitor D. Fixed resistor Answer: B
- In an input-process-output system, which of the following is an output component? A. A light-dependent resistor B. A push switch C. A buzzer D. A thermistor Answer: C
- What is the defining feature of a closed loop control system? A. It uses a battery rather than the mains B. It senses its output and feeds that information back to correct itself C. It has no switches D. It can only switch on and off Answer: B
- An LED needs 2 V at 20 mA and runs from a 6 V supply. What value series resistor is required? A. 100 ohm B. 200 ohm C. 300 ohm D. 400 ohm Answer: B
Available on the Green Bridge App
Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.
Available on the Green Bridge App
Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.
Recommended Books
Practice Mock Questions
Want to practice mock questions on Electronics? Download the Green Bridge CBT app to access mock questions and full practice assessments for this topic.
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