Designing an experiment means turning a question into a plan that gives valid, precise data. Identify the variables, choose equipment with suitable resolution, decide the range, intervals and repeats, and plan how to control or monitor other factors.
Engineering design adds criteria (what the solution must achieve) and constraints (limits such as cost, safety, materials and time). Engineers break a big problem into smaller ones, test prototypes, and compare solutions against the criteria. For example, a cooling device might be judged on how much it lowers temperature, its cost and its energy use.
Worked example
An engineer tests insulation for a cool box. Name one criterion and one constraint.
- Criterion: the contents must stay below 8 °C for 6 hours.
- Constraint: the materials must cost less than a set budget.
Answer:Both guide which design is chosen.
Key words
- criteria
- what a solution must achieve
- constraint
- a limit, such as cost or safety
- prototype
- an early model built for testing
- trade-off
- giving up one benefit to gain another
New questions every time.
NGSS-referenced: HS-ETS1-2