There are a lot of misconceptions related to hydrostatic pressure. One of them is that if you took a jug like the one below (or a U-tube, as in my post on letter tubes and misconceptions around hydrostatic pressure) the water level would have to be higher in the narrow snout of the jug than […]
Who has an understanding of the effect of washing-up liquid on surface tension on a molecular level? Please help! I’ve recently shown a lot of experiments on the topic of surface tension. And while it is a helpful analogy to think of a thin membrane on top of the water that lets water striders or […]
When hydrostatics just doesn’t explain things. Occasionally one notices water levels in straws that are slightly above the water levels in the glass. And of course – even though we always talk about water seeking its level and hydrostatics and stuff – we know that that’s how it should be because of the capillary effects. […]
How to destroy surface tension. Remember how in this post my parents sent me a picture of the experiment that I didn’t get to work out? Later the same day they sent me the movie below, demonstrating first how to put stuff on the surface without it sinking, and then how to destroy the surface […]
Lots of stuff an be made to float on water just because of surface tension. This morning, I was taking pictures of heaps of waters on coins. I was planning to follow up on that post with pictures of a dome of water on a full mug. So far so good. Then, I was planning on putting […]
The classical way of demonstrating surface tension. When talking about surface tension, the classical thing to do is to talk about the shape of drops of water. As seen before in this post, the drops of water act as lenses. It is pretty amazing how much water you can pile on a single coin! If […]
How water striders can walk on water. More pictures from the same spot at the banks of the Pinnau. Looking more closely, you can see the water strider: And now a real close-up from the pond in my parents’ garden (because those pesky little bugs are too fast to take pictures off when you are […]
