SortStack #476 — 2027-09-28

By weight · Order from lightest to heaviest.

1. A sheet of A4 printer paper 5 g

   A-series paper is metric by design: every size is exactly half the one above it, all sharing the same elegant proportions.

2. An adult house mouse 19 g

   Male mice sing ultrasonic courtship songs too high-pitched for humans to hear, with repeated phrases like birdsong.

3. An adult human brain 1.4 kg

   It is about 2% of your body weight yet burns roughly 20% of your energy — mostly just keeping billions of neurons ready to fire.

4. A Thoroughbred racehorse 570 kg

   At full gallop a racehorse's heart pumps roughly 240 liters of blood per minute — ten times its resting rate.

5. ENIAC, the first general-purpose electronic computer 27 t

   Its 17,468 vacuum tubes filled a huge room in 1945. The phone in your pocket is literally billions of times faster.

6. A SpaceX Falcon 9 rocket, fully fueled on the launch pad 549 t

   More than 95% of that is propellant; the reusable first-stage booster lands weighing almost nothing by comparison.

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