A bag of cotton or a piece of pumice rock are excellent examples of low-density objects. Low density means that an object has a small mass relative to its volume. In simpler terms, it's light for its size.
Understanding Density
Density is a measure of how much mass is packed into a given volume. It's calculated by dividing the mass of an object by its volume (Density = Mass/Volume). A low-density object will have a small number when you perform this calculation.
Several references support this understanding:
- American Chemical Society: Points out that comparing the weight of wood to an equal volume of water shows that the wood weighs less, indicating lower density. https://www.acs.org/education/resources/k-8/inquiryinaction/fifth-grade/substances-have-characteristic-properties/lesson-2-4--density-and-sinking-and-floating.html
- Sciencing: Uses examples like oil floating on water (because oil has a lower density) and Styrofoam as illustrations of low-density materials. https://www.sciencing.com/low-density-5151400/
- Purdue University: Reinforces the idea that if something feels light for its size, like a bag of cotton or pumice, it has low density. https://www.purdue.edu/science/K12/LabPages/Density.html
- Energy Education: States that objects with low density have a small mass compared to a large volume, much like an inflated balloon. https://energyeducation.ca/encyclopedia/Density
More Examples of Low-Density Objects:
- Styrofoam: Commonly used in packaging and cups due to its extremely low density.
- Balsa Wood: A very lightweight wood used in model airplanes and other crafts.
- Air: While a gas, air still has a density, though it's very low compared to solids and liquids.
- Helium Balloons: Helium is less dense than air, causing the balloon to float.
