Floating Coins - 3/pk
$1.99
Sale price
$1.99
Regular price
$3.00
Skip to product information
Floating Coins - 3/pk
$1.99
Sale price
$1.99
Regular price
$3.00
At first glance, a 1-yen coin seems unremarkable, but this feather-light aluminum disc is a masterclass in physics and design.
Introduced in 1955, it weighs exactly 1 gram and spans just 20 millimeters. Made of pure aluminum, it’s so low in density that surface tension can hold it afloat on water—an everyday object turned into a physics demonstration. Like ships balanced on the ocean, the coin presses down, but the water’s molecular “skin” pushes back, keeping it afloat.
Place two of these coins side by side and something remarkable happens: they creep together. The scientific term for this is the Cheerios effect, where floating objects bend the water’s surface into tiny slopes, sliding toward one another as though pulled by a miniature gravity.
What began as Japan’s smallest unit of currency has also become a physics favorite, a humble coin that reveals the hidden rules of surface physics while carrying with it decades of economic history.
Includes 3 floating coins
Features:
Deals on this item:
Free Shippingon orders over $50
Your Purchase Does More:
Science Education Programs:Every purchase helps fund our guest lectures, science fairs, and community science clubs — bringing real scientific literacy to curious minds of all ages.
Sustainable Small Business: We partner with agroforestry and carbon capture organizations to keep our entire emissions footprint net negative — not just neutral.
Independent Researchers:We source directly from active research labs, so your purchase puts money back into the hands of working scientists.
