This introduction covers The Suitcase Test 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 1 of 13 in this topic. Use this introduction to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 1 of 13
Practice
13 questions
Recall
30 flashcards
📖 The Suitcase Test
Imagine two identical suitcases — one packed with feathers, the other with bricks. Same size, VASTLY different weights. That difference is density in action. Density tells you how much mass is "packed into" a given space. A small gold ring and a massive gold bar have the SAME density because they're made of the same stuff — density is a property of the MATERIAL, not the object. This is why ships made of steel (density 7800 kg/m³) can float — they're mostly filled with air, making their OVERALL density less than water!
Density Equation
ρ = m / V
Density (kg/m³) = Mass (kg) ÷ Volume (m³)