SortStack #2828 — 2034-03-07

By weight · Order from lightest to heaviest.

1. A standard steel paperclip 1 g

   During WWII, Norwegians wore paperclips on their lapels as a quiet symbol of resistance against occupation.

2. A AA alkaline battery 24 g

   Billions of AA cells are produced worldwide every year, making it the planet's most popular battery size.

3. A liter of water 1 kg

   The kilogram was originally defined in the 1790s as the mass of exactly this much water — the tie was only fully broken in 2019.

4. An adult hippopotamus 1.5 t

   Hippos cannot actually swim — they sink and gallop along the riverbed, surfacing to breathe every few minutes.

5. The International Space Station 420 t

   Assembled over 42 flights, it circles Earth 16 times a day at 28,000 km/h, so its crew sees 16 sunrises daily.

6. The steel arch of the Sydney Harbour Bridge 39K t

   The arch rises and falls up to 18 cm with temperature swings; locals affectionately call the bridge 'the Coathanger'.

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