To measure density, the fundamental approach involves determining the ratio of an object's mass to its volume. This can be done using several methods depending on the state and shape of the material:
- Density formula :
Density=MassVolume\text{Density}=\frac{\text{Mass}}{\text{Volume}}Density=VolumeMass
where mass is measured in units such as grams or kilograms, and volume in cubic centimeters (cm³), liters (L), or cubic meters (m³).
- For regular-shaped solids (e.g., cubes, spheres) :
- Measure the mass using a balance.
- Calculate the volume using geometric formulas (e.g., volume of a cube = length × width × height; volume of a sphere = 43πr3\frac{4}{3}\pi r^334πr3).
- Use the density formula to find density.
- For irregular-shaped solids :
- Measure the mass on a balance.
- Use water displacement method to find volume: submerge object in a measuring cylinder filled with water and record the volume of water displaced.
- Calculate density with the mass and displaced volume.
- For liquids :
- Measure the mass of an empty container, then with a known volume of the liquid.
- Subtract to get the mass of the liquid.
- Use the volume from the container measurement.
- Calculate density.
- Alternatively, use a hydrometer, a device that floats in the liquid and gives a direct density reading based on buoyancy.
- Advanced methods :
- Use of specialized devices like resonator densimeters or MEMS chip sensors for precise density measurements in certain applications.
Overall, the process involves accurate measurement of mass and volume followed by applying the ratio to find density.
