MYP Physics Pressure: How Do You Answer These Questions Well?

Pressure measures how much force is spread over a given area, expressed in Pascals (Pa), where 1 Pa equals 1 newton per square metre. The formula you'll meet in MYP 4-5 is P = F/A — the same force pressing on a smaller area always produces a bigger pressure reading.

Divide the force in newtons by the area it acts on in square metres — the whole calculation is P = F/A. Convert your area into square metres before dividing, because a mixed-up cm²-to-m² conversion is the single most common mark loss I see in MYP assessments on this topic.

Force is a push or pull measured in newtons; pressure is that same force spread over an area, measured in Pascals. Two objects can push with identical force yet produce very different pressures — a stiletto heel and a flat trainer press on a floor with wildly different pressure for exactly this reason.

Pressure in a liquid increases with depth because there's more liquid — and so more weight — pushing down from above. The formula is P = hρg, where h is depth, ρ is density and g is gravitational field strength (9.8 N/kg), so doubling the depth doubles the pressure.

Start every pressure question by identifying the command term, then write the formula — P = F/A or P = hρg — before substituting numbers with correct units. Students who state the formula, show working line by line, and finish with a unit (Pa, kPa or N/m²) pick up every process mark going.

The three mistakes I flag most often on marked scripts: forgetting to convert cm² into m² before dividing, mixing up P = F/A with the liquid-pressure formula P = hρg, and dropping the unit from the final answer — which loses an easy mark every single time.

Pressure questions usually sit under Criterion A (Knowing and understanding) for definitions and calculations, and Criterion C (Processing and evaluating) if you're analysing results from a pressure-versus-depth investigation. The command term — 'state', 'calculate' or 'explain' — tells you which skill the question is actually testing.

Pressure typically appears in MYP 4 or MYP 5 Physics, usually within a unit on forces or fluids — though the MYP doesn't prescribe a fixed syllabus. Schools build their own units around the key concepts and global contexts set out in the MYP Sciences guide, so it's worth asking your school's science department where exactly it sits.

The standard SI unit is the Pascal (Pa), equal to one newton per square metre. You'll also meet kilopascals (kPa) and, occasionally, atmospheres (atm), where 1 atm is roughly 101,325 Pa. Always check which unit a question specifically asks for before you round your final answer.

Yes — pressure in MYP 4-5 lays the groundwork for DP Physics topics like fluid statics and the ideal gas law in Thermal Physics. According to the IB, first exams for the current DP Physics guide were 2025, and students confident with P = F/A and P = hρg move into those DP topics without relearning the basics.

MYP pressure work is conceptual and calculation-based — force, area, and simple liquid pressure using two formulas. DP Physics fluid statics goes further, adding buoyancy, Pascal's principle, and the ideal gas law. Think of MYP as building the toolkit; DP is where your child applies it to genuinely multi-step physical systems.

Not especially — pressure is one of the more approachable numerical topics in MYP Physics because the core formula, P = F/A, is straightforward. Where students actually lose marks isn't the concept itself; it's careless unit conversion and rushing multi-step fluid-pressure questions without writing out each stage of working.

Look for materials that isolate pressure calculations from broader forces topics — separate practice for solid pressure (P = F/A) and fluid pressure (P = hρg), plus a mix of recall and multi-step questions. Worksheets that build from simple substitution up to combined force-and-fluid problems work best for cementing this specific skill.

Sit with your child while they redo one wrong answer step-by-step rather than reading a full worked solution — reproducing the formula, substituting units correctly, and checking the final Pascal value themselves builds the habit examiners reward. A five-minute daily check on unit conversions fixes most persistent pressure errors within a fortnight.