How can changes in pressure on Earth help us find out about Jupiter (and put bubbles in chocolate)?
The vast majority of matter in our solar system, around 90% of it, is subjected to pressures of more than 100,000 times the atmospheric pressure on Earth. This means that what we think of as the ‘normal’ nature of materials actually isn’t very typical.
To find out what materials are like on other planets, a team of physicists at Edinburgh University have been squeezing things – very hard. The extremely high pressures change the nature of the materials being squeezed. For example, oxygen gas turns into a dark red crystal. The team are aiming to turn hydrogen gas into a highly conducting metal which they believe exists naturally deep inside Jupiter.
But it’s not just out in the far reaches of solar system that pressure affects the nature of materials. One of the knottiest problems in confectionery was how to produce a chocolate bar containing a uniform distribution of air bubbles. If you simply bubble air through molten chocolate, the bubbles will rise to the surface of the chocolate before it has had time to cool and solidify.
Fortunately for chocolate lovers everywhere, the problem was solved in 1935 by Rowntree. They developed a method of whisking fluid chocolate to produce lots of tiny bubbles and then placing it in an area of low air pressure whilst it cooled. The low pressure meant that the tiny bubbles expanded, and as they expanded they cooled the chocolate more quickly so the bubbles didn’t have a chance to rise to the surface. The result was light, bubbly and yummy chocolate.
Find related websites about this research with physics.org.