Mass of an average bathtub filled with pennies?

Answer 1

A bathtub can hold about 2 cubic meters of water, we'll say it is half full because no one ever completely fills a tub. A penny is 19mm by 1.27mm thick and i will use a square formation because it is easy to calculate and pennies will not naturally align in the most efficient triangular formation. So each penny takes up about 458.5mm cubed. There are a billion cubic millimeters in a cubic meter so divide a billion by 458.5 and you get 2.18x10^6 or $22,000 in pennies. Pennies before 1982 weighed 3.1 grams and a 2.5 grams afterward. I have 70 pennies and and 18 are pre 1982 so the average penny today is about 2.65 grams. Take that times 2.18x10^6 and you get 5,786,342 grams, 5,786.342 kilograms, or 12,729 pounds. A solid cubic meter of copper weighs 8,960 kilograms. A bathtub can hold about 2 cubic meters of water, we'll say it is half full because no one ever completely fills a tub. A penny is 19mm by 1.27mm thick and i will use a square formation because it is easy to calculate and pennies will not naturally align in the most efficient triangular formation. So each penny takes up about 458.5mm cubed. There are a billion cubic millimeters in a cubic meter so divide a billion by 458.5 and you get 2.18x10^6 or $22,000 in pennies. Pennies before 1982 weighed 3.1 grams and a 2.5 grams afterward. I have 70 pennies and and 18 are pre 1982 so the average penny today is about 2.65 grams. Take that times 2.18x10^6 and you get 5,786,342 grams, 5,786.342 kilograms, or 12,729 pounds. A solid cubic meter of copper weighs 8,960 kilograms.