Did you know that the snow globe was invented by accident?
Around 1900, an Austrian man named Erwin Perzy was trying to build a better light source to use in surgeries, but he ended up with a very different invention instead - a beautiful, handmade snow globe!
Have you ever wanted to make your own snow globe? Well, this month's 20 Minute Lab will show you how, with a little help from the concept of viscosity!
Before we start, you may want to think about what kind of things you want in your snow globe. A winter scene is very common - hence the snow! But you could also make an underwater scene, a zoo scene, or something else - let your imagine run wild! And of course, you can always create more than one!
NOTE: This image shows some different ideas for jars, glitter and toys. Adjust to your taste!
WARNING: If you use epoxy or superglue, make sure to ask an adult for help!
The toys and items you choose should be able to stay in water for a long time without deteriorating (falling apart!). Plastic or ceramic items work great. And be aware that dyes from some toys may color the water. If you're not sure about your items, you could test them out first by leaving them in a bowl of water for a day or so before you make the globe. Avoid metal, as it will rust, and wood, as it may discolor the water.
What's going on?
What makes the glitter (snow) fall slowly through the globe? How things flow has to do with viscosity. Viscosity is a measure of how "thick" a liquid is.
Water has a low viscosity, meaning it is a rather "thin" liquid. In other words, glitter moves around very easily when you stir it in water! But glycerin, as you noticed in the experiment, is thicker; it has a higher viscosity. You likely noticed that, even when vigorously stirred, the glitter barely moved in the glycerin!
Adding water to the glycerin creates a liquid with a medium amount of viscosity. That way the glitter falls slowly, more like snow, rather than staying suspended for hours (as it would if you only used glycerin without any water)!
Can you think of other viscous fluids? How about molasses or honey? Those are pretty thick!
Glycerin is a nice choice for snow globes because it is clear. It's also water soluble, meaning it mixes well with water, instead of remaining separate.
Glycerin is also only a little bit more dense than water, again making it so they mix well together. Density refers to how much stuff can be packed into a given space. To learn more about density, check out the 20 Minute Lab: Rainbow in a Jar.
SHARE WITH US!
For more exciting experiments, check out our Yellow Scope Science Kits on the Shop tab of our website!