3 HN users recommended this explainer3 months2015–2021score 3.5
Years with an HN recommendation, 2007–2026
HN uses it as the go-to demonstration of how unintuitive mass conservation is, especially in weight loss and burning threads.
Veritasium asks people where a tree's mass comes from, then explains that most of a dry tree's mass originates from carbon dioxide in the air. It combines street interviews with a short explanation of photosynthesis.
“Veritasium has a fun video demonstrating how unintuitive this is” (HN, 2017)
There's a nice Veritasium episode wherein he asks people on the street where a tree's mass comes from: [this video] (This isn't just one of those "let's laugh at how dumb people on the street are" videos; it's done explicitly as a learning exercise. His PhD looked at how addressing misconceptions and going from there to correct explanations works much better than simply providing explanations: [link] ) I thought of it upon seeing the first chart in the BMJ article.)
Street interviews on where tree mass comes from, as a learning exercise.
And the reverse biochemical process is equally misunderstood. I used to teach high school Science and everyone thought a tree's mass came from the soil. [this video]
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