Try a heavier, curvier rock when skimming stones, scientists say
Published: Jan 05, 2023 05:39 PM
Want to make an impression the next time you're trying to skim a stone off water? Ignore the usual thin, flat candidates and try a fatter, curvier rock to get the biggest possible bounce, scientists said Wednesday.

People have been skimming stones across bodies of water for centuries - at least - and any experienced skipper knows that rock selection is crucial. While thin, flat stones still give the greatest chance of a maximum number of skips, Ryan Palmer, a mathematician at the UK's Bristol University, said that "you can get these new exciting dynamics out of rocks that you typically reject." Fatter, curvier stones offer something "that's completely different, but just as spectacular: huge leaps out of the water," he told AFP.

The new research, published in the journal Proceedings of the Royal Society A, uses a physics-based mathematical model to crunch centuries-old equations on a computer. They found that a heavier rock gave a "super-elastic response" that produced an "almighty jump," he added.

When the stone hits the water, horizontal velocity turns into vertical velocity, so it makes sense that a heavy rock would put more force into that interaction, he said.