Paper
Sold by weight per area rather than thickness — 80 gsm office paper is about 0.1 mm thick, which works back to roughly 800 kg/m³, denser than pine and lighter than water. It is strongly directional: the fibres align with the machine direction during manufacture, so paper tears cleanly one way and raggedly the other, and that is what decides which way a page curls in a damp room. It does not melt; it browns and chars from around 150 °C and self-ignites near 230 °C — which is 450 °F, the number Bradbury rounded up by one.
Properties
- Density
- 800 kg/m³ (600–1,000) — 0.80 g/cm³
- Tensile strength
- 20–60 MPa
- Floats in water
- Yes
- Magnetic
- No
What it is used for
- Printing and writing
- Packaging and labels
- Filtration and absorbent products
- Insulation in transformers and cables
How it compares
Water is 1,000 kg/m³. Anything with a shorter bar than water floats in it.
| Material | Density | Relative to water |
|---|---|---|
| rigid polyurethane foam | 40 kg/m³ | 0.04× |
| expanded polystyrene foam | 20 kg/m³ | 0.02× |
| air | 1.2 kg/m³ | 0.00× |
| paper ← | 800 kg/m³ | 0.80× |
| platinum | 21,450 kg/m³ | 21.45× |
| gold | 19,300 kg/m³ | 19.30× |
| tungsten | 19,250 kg/m³ | 19.25× |
Does it rust?
Paper contains no iron, so it cannot rust. Whether it degrades depends on the material, not on oxidation.
Is it magnetic?
Paper is not a metal and has no ferromagnetic response.
Common questions
- What is the density of paper?
- 800 kg/m³ (600–1,000), or 0.80 g/cm³.
- Does paper float?
- Yes. At 800 kg/m³ it is less dense than water's 1,000.
- Is paper magnetic?
- Paper is not a metal and has no ferromagnetic response.
Related pages
- Does paper float? Yes
- Air 1.2 kg/m³
- Ice 917 kg/m³
- Corrugated cardboard 160 kg/m³
- Cork 200 kg/m³
- Leather 900 kg/m³
Sources
- Typical range compiled from manufacturer specifications — At One Place