SQA / QS Higher
Higher Engineering Science revision
Revision notes, key terms, practice questions and worksheets for every SQA / QS Higher Engineering Science topic: systems and control, energy, electronics, mechanisms, pneumatics and structures. Choose a topic.
Engineering contexts & challenges
- The systems approach & controlAny system can be shown as a universal system diagram: input → process → output. A sub-system…
- Energy & efficiencyEnergy can't be created or destroyed, only changed from one form to another. In real systems some…
- Engineering roles & disciplinesDon't mix up electrical (power) and electronic (control circuits): the 2025 N5 report flagged this.
- Impacts of engineering & emerging technologySocial (people's lives): health, safety, convenience, jobs and skills, noise, community. E.g. an…
Electronics & control
- Components, Ohm's law & resistor networksCurrent (I) is the rate of flow of electric charge, measured in amps (A). Electrons flow from − to…
- Voltage dividers & sensorsTwo resistances in series across a supply share the voltage in proportion to their resistance: the…
- Transistors, relays & MOSFETsAn NPN transistor has a base, collector and emitter. When the voltage at the base is about 0.7 V or…
- Operational amplifiersAn op-amp amplifies the difference between its two inputs: inverting (−) and non-inverting (+). It…
- Digital logicAND: output 1 only when all inputs are 1. Boolean A·B.
- Microcontrollers, flowcharts & programmingA microcontroller is a small programmable computer on a chip, with inputs and outputs, used in…
Mechanisms & structures
- Drive systems & mechanismsA mechanism changes an input motion and force into a different output motion and force: it makes a…
- PneumaticsSingle-acting cylinder: air outstrokes the piston; a spring returns it.
- Structures & forcesTension pulls a member (it would stretch); a member in tension is a tie.
- Materials, stress & strainSelect from a table of properties and justify with properties linked to the job: "Material C…