Self-tutoring about birds and ecology: the tutor mentions ravens and crows. The competitive exclusion principle states that two animals cannot occupy the same niche – ie, role – in the same environment: one always out-produces the other, and takes sole …
Self-tutoring about chemistry: the tutor mentions nuclide. A nuclide is more specific than an atom – it’s closer to the idea of an isotope. An atom is identified by its number of protons, aka its atomic number. Yet, the type …
Self-tutoring about past events: the tutor reflects on the last lab course he took. Chemistry was my favorite subject in grade 12. I had planned to take a chemistry/biochemistry degree at university, so in first and second year I took …
Self-tutoring about chemistry: the tutor learns about helium and its sources on Earth. Apparently helium is the second-most abundant element in the universe (while hydrogen is first). Where is helium found on Earth? It turns out that most helium is …
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Self-tutoring about radioactive decay: the tutor wonders what happens to emitted alpha particles. An alpha particle – sometimes written α – can be emitted in various radioactive decay scenarios. U238 → Th234 + α is an example. α particles aren’t …
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Self-tutoring about electronic lifestyle: the tutor mentions checking what the camera is doing, Windows 10. Clicking the Start button lower left, a scroll list of apps appears: one is Settings. Clicking that, the Settings app will open. You may have …
Electronic lifestyle: what is your camera doing (Windows 10)? Read more »
Self-tutoring about file types: the tutor mentions a new one he’s encountered. Downloading a zip file, I thought it was done, so opened the downloads folder. There were two new ones – unconfirmed_[some digits].crdownload as well as the_file.zip. Naturally I …
Self-tutoring about the Bible: the tutor makes a first look at Purgatory. I read the Bible, cover to cover, two years ago. I don’t recall seeing the word Purgatory. Did I overlook it? At least two sources suggest that no, …
Self-tutoring about airships: the tutor compares the lifting power of helium and hydrogen. Helium’s atomic mass is 4.0, while hydrogen’s is 1.0. However, hydrogen is diatomic, meaning it will only exist, by itself, as H2, bringing its mass to 2.0 …
Self-tutoring about strength among animals: the tutor looks into a strength comparison between chimpanzees and humans. I’ve heard, numerous times, that chimpanzees are stronger than humans. “Small wonder,” I thought. “In our society, humans are sedentary, whereas chimpanzees are wild …