--- title: "Systems: Input, Process, Output" description: "Describe a product with an input-process-output block diagram: what enters, what happens inside the chosen system, and what leaves. Use observations and checks to narrow down possible fault locations," canonical: https://lightmysky.com/learn/design-and-technology/systems-input-process-output-mt_bMNTQ-3a_u source: https://lightmysky.com/learn/design-and-technology/systems-input-process-output-mt_bMNTQ-3a_u.md retrieved: 2026-11-12 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # Systems: Input, Process, Output Describe a product with an input-process-output block diagram: what enters, what happens inside the chosen system, and what leaves. Use observations and checks to narrow down possible fault locations, and explain how feedback helps control a system. Subject: Design & Technology · Area: Designing & Making · Ages 12 to 14 Page: https://lightmysky.com/learn/design-and-technology/systems-input-process-output-mt_bMNTQ-3a_u ## Ready when they can - Draw a block diagram for an everyday product with the three stages labelled - Use a block diagram and stated test evidence to identify a likely fault stage or explain what further evidence is needed - Explain what feedback adds to a system, using a thermostat or a cruise control - Say why the same diagram fits a kettle and a phone app ## Lesson: Model a product as a system A block diagram models how a product works. Choose what your system includes. Draw boxes labelled input, process and output, then join them with arrows in that order. Input is what enters, such as material, energy or information. The process is what the system does. Output is the result that leaves. The diagram leaves out details that are not needed for your question. **Example.** For a kettle, water and electrical energy are inputs, heating is the process, and hot water is the output. For a phone app, taps and data are inputs, the program's work is the process, and displayed results are outputs. A toaster also needs electrical energy: bread and electricity enter, heating browns the bread, and toast is the food output. *(drawing: These boxes name the stages in the kettle model. Read them from left to right.)* Feedback uses information about a measured result to adjust a running system. A thermostat compares room temperature with a chosen temperature and controls the heater. Cruise control compares measured speed with the chosen speed and adjusts the car's driving force. A design iteration changes a prototype between tests; automatic feedback adjusts a system while it runs. A symptom can have several causes. If correct input data and a clean processed signal reach a speaker, but its sound is distorted, investigate the output stage first. A diagram alone does not identify a failed component. Use supplied checks or simulations for fault tracing. Do not open mains appliances, work on live circuits or test moving vehicles. No supply at a lamp's plug means missing input, not proof of an internal lamp fault. **Recap.** Label input, process and output for a chosen system. Feedback uses measured results to adjust it. Use supplied test evidence to trace possible faults safely. *Original lesson, questions and flashcards written for this dataset about system models, feedback and evidence-based fault tracing.* ## Practice 8 questions on this page, each with its working shown. ## Needs first - [Drawing a design so someone else can build it](https://lightmysky.com/learn/design-and-technology/drawing-a-design-so-someone-else-can-build-it-mt_8ezErqUhZw) ## Optional connections - [Electronics in a Product: Switch, Sensor, Output](https://lightmysky.com/learn/design-and-technology/electronics-in-a-product-switch-sensor-output-mt_KNLW4qke5J) ## Opens up - [The Whole Life of a Product](https://lightmysky.com/learn/design-and-technology/the-whole-life-of-a-product-mt_hyBZiDvDoX)