Core Science
What the domain tests
MATSEC SEC Core Science is a single integrated subject. It tests whether you can use biology, chemistry, physics and earth science ideas to explain familiar situations, interpret data and describe safe practical work. Questions ask you to name processes, choose units, complete tables, read graphs and justify conclusions, not just recall definitions.
Core rules and concepts
- SI units: length in metres (m), mass in kilograms (kg), time in seconds (s), force in newtons (N), energy in joules (J), power in watts (W), voltage in volts (V), current in amperes (A), resistance in ohms (Ω). Convert cm → m (÷100), g → kg (÷1000), minutes → s (×60).
- Fair testing: change one independent variable, measure the dependent variable, keep control variables constant, repeat readings and calculate a mean.
- Particles and reactions: solids, liquids and gases differ in particle arrangement and movement; filtration, distillation and chromatography separate mixtures; chemical reactions form new products and conserve mass.
- Living processes: photosynthesis stores energy (carbon dioxide + water → glucose + oxygen); respiration releases energy in all living cells; enzymes are biological catalysts.
- Forces and circuits: speed = distance ÷ time; density = mass ÷ volume; work = force × distance; power = work ÷ time; series current is the same throughout, parallel current splits; V = IR for an ohmic component.
Worked example
A cyclist travels 150 m in 10 s. Average speed = distance ÷ time = 150 m ÷ 10 s = 15 m/s. Convert to km/h: 15 × 3.6 = 54 km/h. Show the formula, substitute with units, then state the unit.
Traps that cost marks
Do not write weight in kilograms - weight is a force in newtons. Plants respire as well as photosynthesise. Current is not “used up” in a series circuit. A control variable is not a control group. Always give units and read graph axes before quoting a gradient.