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A new video every Sunday from the kitchen table and the balcony: one thing, measured.
How far away is the moon? A ball and a walnut
A ball the width of a hand and a walnut three metres apart show how far away the moon really is.
How tall is a tree? Measuring with a shadow
A torch, a stick and two shadows are enough to measure something far taller than you can reach.
How many grains of rice fill a jar?
Count one spoonful, count the spoons, and find out how big a number you can reach without counting every grain.
How thin is a hair? A drop of water as a magnifier
A hair is about a tenth of a millimetre across. A drop of water on a phone camera lets you see it.
A Number a Week
A short letter every Sunday with one number from the week's video, how I found it and how you can find it too.