Scientists have solved the riddle behind one of the most recognisable and annoying household sounds: the dripping tap. And, what's more, they say squirting washing up liquid in the sink solves the maddening problem in seconds. Using ultra-high-speed cameras and modern audio capture techniques, researchers showed the'plink, plink' is not caused by the droplet itself hitting the water. Instead it's the waves, or oscillation, of a small bubble of air trapped beneath the surface. Researchers from the University of Cambridge's department of engineering used an ultra-high-speed camera, a microphone and a hydrophone to record droplets falling into a tank of water.
A mesmerising video shows the moment a water droplet bounces off a surface and is made to spin at more than 7,300 revolutions per minute (RPM). The properties of a droplet change depending on what it hits and scientists have manipulated this process to make them gyrate. Scientists say the findings could allow for future developments for hydro-energy collection, self-cleaning and anti-icing. Researchers from the Institute of Chemistry, part of the Chinese Academy of Sciences, say the observed process opens up a promising avenue for the delicate control of liquid motion. Huizeng Li and colleagues published the research in the journal Nature Communications and write in the abstract: 'Droplet impacting and bouncing off solid surface plays a vital role in various biological/ physiological processes and engineering applications.
It haunts you when you're trying to eat your dinner in peace. It disturbs you when you're trying to watch TV. It even keeps you awake in the wee small hours. It's the insufferable, interminable drip-drip-dripping of a leaky tap. Well, scientists at the University of Cambridge have finally figured out what's causing what is almost certainly the world's most infuriating sound.
It's the sound of water droplets falling one after another, maybe from a leaky faucet or through a cracked ceiling. It's the kind of sound that can keep you up all night. University of Cambridge engineer Anurag Agarwal feels your pain. While visiting a friend in Brazil in 2016, Agarwal couldn't ignore the water that steadily dripped through the leaky roof and fell into a bucket below. "It was a rainy period, and the downfall was torrential," he says.
A summer rain falling on a barley field is the very picture of vitality. The shower softens the dry ground; crops grow tall; grain fattens and is harvested to make bread, or beer, or feed for livestock. But zoom in close and you may witness a strikingly different scene: The same raindrops that bestow life can also spread disease and death. Just as the common cold can travel through a handshake or a cough, plant epidemics move in various ways--by breezes or bugs, soil or seeds. Many bacteria and some types of fungal spores also jump from leaf to leaf in splatters of rainwater, a plant's version of a sneeze.