Learning means more than studying a new subject. It’s as much about enlightenment, and building your understanding of something you already know. In some cases, exploring a subject further can actually disprove something you once believed to be true.
When I was a child, I remember accidentally leaving water bottles in the freezer too long and noticing how much they expanded when they froze. Later, I remembered observing the ‘tip of the iceberg’ phenomenon when I looked at ice cubes floating in drinks. Most of the ice was beneath the surface, as is the case for icebergs in the ocean. One day, I recall hearing someone talking about global warming and rising sea levels, citing melting icebergs as the primary source of the extra water. This notion just didn’t seem right to me.
If water expands when it freezes, and only a very small amount of ice sits above water when it floats, would these two volumes be equal? In other words, does ice actually raise the level of water when it melts? There was no Internet in those days, and it was a Friday night when I decided I needed to answer this problem immediately. So I did an experiment.
I poured water into a glass then added an ice cube and marked the water level. I let it melt then checked the water level. You guessed it, the level was the same.
I later learned other reasons why melting ice causes sea levels to rise, but at the very least, my experiment had proven that it wasn’t simply caused by melting icebergs. I could have just taken that statement as gospel, but I wanted to see the phenomenon in action.
That is what I mean when I talk about moving beyond just knowing something. Beyond knowledge lies understanding. To explain why melting ice doesn’t change the water level in a glass requires an understanding of the phenomenon.
Why does ice float? Because it is less dense than liquid water. There are just as many water molecules in an ice cube as there are when it melts, but when frozen, there is more space between the molecules, so it occupies more space for the same number of molecules. You can even watch a good video about it here.
Some probably call this ‘discovery learning’ or ‘applied learning’. I call it ‘moving beyond knowing’. Whatever you call it, it sure beats memorising facts!
Is there something you’ve heard recently that you doubt, and want to disprove? Let me know in the comments.