Interactive · 2 questions
Before we get started, let's have a quick quiz!
Which term is used to describe the amount of "stuff" something has?
Which term is used to describe the amount of space something takes up?
If you got both of those questions right on the first try, you're either already a master at this or you just got lucky! Let's go over the relationship between mass, volume, and density.
Mass
Above, I defined mass as the amount of "stuff" something has. What does that mean? Well, mass is really defined as the amount of matter something has. You can think of matter as anything that occupies physical space. So, in layman's terms, mass is really just how much "stuff" something has! Here on Earth, we use mass to determine weight. Go to the physics section if you want to find out more about this!
Volume
Volume is a little easier to understand. Let's say you have a beaker of water that is filled to the 500 mL mark. '500 mL' is really a way of quantifying (describing using numbers) how much space that water is taking up. So, we can define volume as the amount of space that an object takes up.
Now let's get the difference between these two straight! Say you have a bowling ball. The bowling ball may not look that big, but when you pick it up, it's really heavy! That's because it has a lot of "stuff", or matter, so we can say that it has a large mass. Pick up a grapefruit that's about the same size as a bowling ball. It takes up about the same amount of space, so the ball and the fruit have the same volume. However, does the grapefruit feel as heavy as the bowling ball? No, it hasn't got quite as much "stuff" in it. Therefore, the grapefruit isn't quite as massive as the bowling ball.
Density
We can describe the ratio of how much "stuff" there is per unit of space as density. The equation for density is:
(if you can't remember this, write it out - m/v looks like a heart!)
Now we can prove that the bowling ball is more dense than the grapefruit - that is, it has more "stuff" per unit of space. This may sound pretty simple, but it's a crucial building block for other important concepts in physics and thermodynamics!