Have you ever wondered what would happen to a deflated ball if you put it in a vacuum chamber? I think most of us would guess that the remaining air inside the ball would cause the ball to inflate as the pressure dropped around it. And that is exactly what happened in the latest episode of the Will it Bloat? series of videos from GNB Group – a US-based supplier of vacuum components.
The video is presented in the style of a cheesy American game show by Ken Harrison, president and CEO of GNB. His amiable sidekick is the firm’s chief financial officer Chris Long – who explains why the duo are putting a random selection of objects into a vacuum chamber.
Harrison and Long have so far made 22 episodes of “America’s favourite vacuum game” so I cannot describe all of them. But here are some evacuated objects that I particularly enjoyed: a chocolate Easter bunny; a glass of root beer; and a bell pepper. Any guesses on which objects bloated?
You can find all the Will it Bloat? videos here.
Trees in motion
Trees seem like solid, static things – at least over the course of a day. Sure, their branches and leaves might get blown around by the wind, but they don’t really change that much – or so I thought.
It turns out that tree branches and leaves can droop by as much as 20 cm during the night. Now, researchers in Finland have used laser remote sensing systems to measure this droop in 3D to millimetre accuracy. Furthermore, they have concluded that the droop occurs because branches and leaves replenish their supplies of water at night – and the extra weight pulls down the boughs.
The team plans to develop their technique so it can be used to understand how trees respond to the changes in the availability of water. They also say that the system could be used to monitor plants in greenhouses to avoid wasting water.
You can find out more in this open access paper in the journal Forests: “Tree water status affects tree branch position”.
Squashed doughnut
We were all excited here at Physics World to see that image of the supermassive black hole at the centre of the Milky Way – which was released by the Event Horizon Telescope yesterday. The image – which is not really of the black hole, but rather of the region surrounding it – looks so much like a squashed doughnut that memes started to appear on social media before the news conference was even over.
Today (Friday the 13th), the folks at Krispy Kreme are celebrating the image by offering a free doughnut to anyone who asks. Unfortunately the offer only applies in the US. That is bound to cause traffic jams throughout the country as people scramble to claim their doughnut. So perhaps it is time to hand traffic-light management over to an artificial intelligence system developed at the UK’s Aston University.
