Finding the density of regular shapes, irregular objects and liquids, with repeats, anomalies and uncertainty.
What you will learn
- Measure the volume of a regular solid and of an irregular object
- Find the density of a liquid
- Use repeats, anomalies and the range to judge results
Three kinds of object
You always need a mass (on a balance, zeroed first) and a volume.
- Regular solid: measure the length, width and height with a ruler or callipers and multiply.
- Irregular solid: lower it on a thread into a measuring cylinder of water. The rise in level is its volume. This is measuring volume by displacement: the object pushes aside (displaces) its own volume of water. For a big object, use a eureka can and catch the water that overflows.
- Liquid: weigh an empty measuring cylinder, add a known volume of liquid, weigh again. The difference is the mass of the liquid.
volume of object = volume after − volume before
The rest of this lesson and its 9 practice questions are locked.
In this lesson
- Three kinds of object
- Getting good readings
- Try it: Displacement with numbers
9 practice questions, marked as you go; about 25 minutes in all.
In this unit: Particle model, density and gas pressure
Density and its required practical, changes of state, specific latent heat, and the particle model of gas pressure, including p₁V₁ = p₂V₂.