Why do some things sink and some things float in water? The ability of an object to float in a liquid or gas is called buoyancy (ask your parents to help you pronounce it!). Whether or not something sinks or floats depends on the density of the object compared to the density of what it is floating in. Density is a term that describes how much of something is in a given space. For example, an elevator with 11 people in it is more dense than the same elevator with only 3 people in it. A suitcase that is completely packed and filled to the brim is more dense than an empty suitcase. Buoyancy pushes an object up through water if the object is less dense than the water.
Watch the following video and in the comments section, write one thing you learned about density, and one object that YOU would like to test for density to see if it floats or sinks!
Watch the following video and in the comments section, write one thing you learned about density, and one object that YOU would like to test for density to see if it floats or sinks!