This definitions covers Key Definitions within Density for GCSE Physics. Revise Density in Particle Model for GCSE Physics with 13 exam-style questions and 30 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 7 of 13 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Topic position
Section 7 of 13
Practice
13 questions
Recall
30 flashcards
📖 Key Definitions
Density (ρ): The mass per unit volume of a substance. ρ = m/V. Units: kg/m³ or g/cm³.
Mass (m): The amount of matter in an object. Measured in kilograms (kg). Does not change with location.
Volume (V): The amount of space an object occupies. Measured in m³ or cm³.
Displacement method: A technique for measuring the volume of an irregular solid by submerging it in water and measuring the volume of water displaced.
Upthrust: The upward force exerted by a fluid on a submerged object, equal to the weight of fluid displaced. If upthrust equals weight, the object floats.
Quick Check: A rock has a mass of 270 g and a volume of 100 cm³. What is its density in g/cm³?
Density = mass ÷ volume = 270 ÷ 100 = 2.7 g/cm³. This matches aluminium — the rock is likely granite or similar.