Blog Archives

The Five Second Rule: A Simple Everyday Question Leading To Quantum Mechanics and Biology

Sometimes the simplest question can lead down a deep rabbit hole to new worlds. How fast germs contaminate food that falls on the floor is a good example of such a question. When you start to think about it, you realize that you don’t quite now what it means for two objects to touch, and when you start analyzing the microscopic and then the quantum mechanical details, you cross multiple scientific disciplines.

This is the intellectual journey that Michael Stevens goes on in his video that debunks the “five second rule,” a popularly held belief that food that falls on a dirty floor is safe to eat if it is picked up quickly enough. One of the main benefits of this type of video is its ability to connect seemingly unrelated issues and motivate viewers to conduct their own thought experiments. You may think it’s a silly question, but you’re sure to be surprised by at least some aspects of the answer.

A Collection of Natural Science Demonstrations from Harvard

Science often feels like a magic show and that aspect makes it particularly appealing to science education. Great communicators of science like Walter Lewin can enchant any audience by turning ordinary physical phenomena into captivating demonstrations that violate intuition and tickle imaginations. In this tradition, Harvard University has created a collection of science demonstrations and simulations covering chemistry, physics, and astronomy. Some of these demonstrations are hard to replicate at home or even in a regular school classroom because of the complex equipment requirements, which is why putting them online is so beneficial. Below is an example of one of the demonstrations that features Chladni plates. More videos are available on the Harvard Natural Sciences Demonstrations Youtube channel.

Lively Chemistry Crash Course for Those in a Hurry

Although chemical experiments can yield exciting results, the theoretical part of chemistry may appear overly dry to students who are not already interested in it. Those who are studying the subject and need to review it may be overwhelmed by the sheer volume of details that they need to memorize. In both of these cases, it is helpful to have a highly condensed and lively summary of the key concepts. That is exactly what Hank Green accomplishes in his video series, Chemistry Crash Course. The videos in this series are short and entertaining, but they still highlight fundamental concepts. You can think of the collection as an extended trailer for the much broader and deeper subject or as a fun way to review for a chemistry test. The videos do not replace a textbook or a good teacher but they pack enough content into a few minutes that we recommend pausing them to process all of the information. If you have encountered any chemistry at all, these videos will be a bit more useful than if you have never heard about the existence of atoms.

A Quick Look at the Biochemistry and History of Modern Frozen Food

Most of us know that freezing food prevents it from spoiling, but the fact that quick freezing is better than slow freezing is a more subtle point that not everyone may know. As always, Henry Reich delivers a to the point video that addresses this issue and illustrates the science behind modern frozen food. As usual in such videos, some details need to be skipped, but there are enough scientific nuggets here (if you pause it) for further exploration. Even if you don’t take the time to learn about the Arrhenius equation, you will be much more appreciative of modern refrigeration.