How do I find the volume of a rock? - Answers

Irregularly shaped objects have no formula for finding the volume. So, to find the volume of a rock, one method is to measure how much water the rock displaces. You simply need some sort of container that measures the volume of liquids and you need some water. The container should be large enough to put the rock in. First, fill the container to a certain volume, noting what that volume is and making sure that enough water is used to completely cover the rock when you put the rock in the container. Next place the rock into the container and measure the new volume indicated by the water. Subtract this new volume with the old volume, and the answer will be the volume of the rock. Another method is to use the rock's mass and density to calculate the volume. This can be tougher because you might not know what type of rock you have and many rocks are composites of different types of rocks. Some internet websites give the densities of different rocks. The website http://www.earthsci.unimelb.edu.au/ES304/MODULES/GRAV/NOTES/densities.html gives some simple densities. But if you have all this information, the volume can be determined by measuring the mass of the rock and dividing that number by the density.