I recently heard the word 表面張力 (pronounced “hyoumen chouryoku”) on a science-related podcast and at first I was completely clueless but after hearing an example usage or two I managed to guess the meaning.
I’ve mentioned this in another post or two, but one of the great things about Japanese is that you can guess word meanings just from looking at the Kanji, or by guessing which kanji are used from their sounds when listening. For those of you who don’t know the meaning of this term let’s try to guess it’s meaning from the Kanji. Here is a list of the individual characters and their general meanings (using this site):
表 – surface, table, diagram
面 – face, features, mask, surface
張 – spread, stretch, lengthen
力 – power, strain, exert
Any guesses? If you still aren’t sure, check out this page which shows a kid’s experiment about 表面張力. The picture near the bottom will likely tell you the answer even if you don’t understand much of the Japanese. Another hint – the word 表面 by itself means “surface”, though from the kanji meanings you probably already guessed that.
The answer is “surface tension”, which is a pretty advanced scientific term so some of you may not be familiar with it, or know exactly what it means. Here is the basic definition taken from wikipedia:
Surface tension is a contractive tendency of the surface of a liquid that allows it to resist an external force.
A example of this, shown in the childrens experiment page I referred to above (here) ‘s when you have a glass filled with water and a tiny layer of water develops on the top above the cup which normally you would think is impossible since the water should overflow. Surface tension is what is causing this effect.