photosynthesis

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.

A short clip from a Richard Feynman interview in which he explains fire, describing how burning wood releases sunlight stored by the tree, which built itself mostly from air. It showcases his curiosity and plain-spoken explanations.

Dr. Bruce Bugbee walks through the calculations for crop yield potential when light is the limiting factor, from photosynthetic quantum yield through respiration efficiency and harvest index, using the Energy Cascade Model.