P5: Matter, Hydrostatic Fluid Pressure and Ideal Gases
Official Cambridge & Imperial ESAT specification requirements for Matter, Hydrostatic Fluid Pressure and Ideal Gases on the Physics paper. Understand the syllabus boundaries, spot distractor traps engineered by examiners, and master the 2-step Sub-90 shortcuts that compress solve time well below the 88.8-second cutoff.
Official Syllabus Subtopics
Requirements specified in the UAT-UK framework
- 1Density definition: ρ = m/V and composite alloy mixtures
- 2Hydrostatic pressure in fluids: P = ρgh
- 3Atmospheric pressure and total pressure Pₜₒₜ = P(atm) + ρgh
- 4Archimedes’ principle and buoyant upthrust: F(up) = ρ(fluid) × V(submerged) × g
- 5Floating equilibrium: F(up) = weight ⟹ ρ(object) / ρ(fluid) = V(submerged) / V(total)
- 6Boyle’s law: P₁V₁ = P₂V₂ at constant temperature
- 7Pressure law: P/T = const and Charles’s law: V/T = const (Kelvin scale)
- 8Ideal gas equation: PV = nRT and kinetic model of gas pressure
Sub-90 Exam Speed Tips
How top candidates solve this spec under the 88.8s clock
Upthrust depends solely on the density of the FLUID displaced and the submerged volume, NOT the density of the submerged object.
Always convert temperatures to Kelvin (T(K) = T(°C) + 273) before calculating gas pressures or volumes.
Examiners engineer distractor options using common algebraic expansions and sign slips. Always test structural ratios or invariants before calculating arithmetic values.
Tested Topics in Specification P5
Master the individual question patterns and Sub-90 shortcuts for this specification.
Hydrostatic Fluid Pressure (P = ρgh), Archimedes Upthrust, Composite Density & Ideal Gas Pistons (P(1V, 1) = P(2V, 2))
Isothermal gas shortcut: since P*V = const and ρ = m/V, gas density ρ scales directly with absolute pressure: ρ₂ / ρ₁ = P₂ / P₁ = (P(atm) + mg/A) / P(atm).
Ready to Master Specification P5 Under Exam Conditions?
Practice timed questions under the authentic Pearson VUE interface with live split stopwatch pacing, dry-wipe scratchpad, and distractor forensics.