Powers of 10

Algebra 1 · Axiom Academy

Powers of 10: A Journey Through Scale From a single proton to the whole observable universe — one idea measures it all. A proton is about 10^ -15 metres across; the observable universe is about 10^ 26 metres . Writing all those zeros out by hand is hopeless — so we count in powers of 10 , where every step up the ladder simply multiplies the size by 10 . Drag the slider to change the exponent. Each notch is one power of 10 — ten times bigger to the right, ten times smaller to the left. Watch the object, the zeros, and the scientific notation move together. Why bother with scientific notation? The Sun is about 93 billion metres from where its light spreads thin; an atom is about a ten-billionth of a metre. Hit Play and watch those zero-stuffed numbers collapse into something you can actually read. The exponent is the story: a positive power counts the zeros of a number bigger than 1, a negative power counts the decimal places of a number smaller than 1, and every step is just another ×10 . That one idea stretches from a proton to the universe — and it's why scientists, engineers, and your calculator all write huge and tiny numbers as powers of 10.

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