This October Earth will be passing through the tail of Halley’s comet, which will mean a shower of meteors flashing across the night sky. Our science editor Sam Gouldson explains.
What is Halley’s Comet?
A comet is a lump of rocky particles, ice and dust all bound together like a dirty snowball. When the comet nears a star, its surface transforms from a solid to a gas. The star’s light shines through these gases and makes them visible to observers as a fuzzy cloud around the comet’s centre, and a tail streaming out behind.
When we talk about electric batteries, we often talk about voltage. But did you know that this word is named after the person who invented the first electric battery? First, let’s take a look at what a volt is, and then we’ll find out more about the guy who gave the ‘volt’ its name.
What is a Volt?
A volt is defined as a unit of electric potential and electromotive force, and voltage refers to the number of those units. That sounds a lot more complicated than it is! If you think of the water in a tap being like the electricity running through a wire, the voltage means the amount of pressure. This video is quite long but explains it very well.
Why are Volts Called Volts?
Alessandro Volta
The term actually comes from a name. It was coined in honour of Italian physicist Alessandro Volta, who is recognised as the inventor of the first electric battery. During the 1790s, Volta worked on the theories of electricity of the day.
Volta disagreed with the theory proposed by fellow Italian scientist Galvani that electricity was generated by animal tissue. Instead of experimenting on frogs or other animals, Volta did experiment after experiment with metals.
His persistence paid off, and in 1800, he invented the world’s first battery, known as the ‘voltaic pile’.
The Voltaic Pile
This voltaic pile was simple but ingenious. It consisted of a pile of zinc and silver discs. But alternating between them was a piece of cardboard, or a piece of cloth, that had been soaked in saltwater.
There was a wire that connected the zinc disc on the bottom to the silver disc on the top, and this wire was capable of producing sparks.
What else Did Volta Invent?
The invention of the first electric battery brought Volta the most fame and recognition, but he also made other discoveries. He invented the electrophorus, a device that could transfer an electrical charge to other objects, as well as an electrical condensor, and the voltaic cell.
He is also known for having discovered and isolated methane gas. After his death, the volt and voltage were named in his memory.
What about Galvani?
Luigi Galvani
Yet there is one more twist to the tale. Volta’s longstanding colleague Galvani of the animal electricity theory also left his name in our language. When we say ‘galvanise’ or ‘galvanism’, that is where it comes from.
Despite their differing theories, there was no rivalry between the two scientists. They were both more concerned with the pursuit of knowledge than with whose theory would prove to be right, and it was Volta who first coined the word ‘galvanismo’ in Italian.
Have you ever visited Egypt? Or even just travelled in your imagination to see the pyramids and the Sphinx? Well, now we are going to travel back in time along the path of the word itself, to see where it came from.
Rosie wrote an article last week for Jump! Mag, telling us about her life on a farm. What you did not know when you read that piece, is that Rosie has special needs. Her mother explains how it is to live with a child with special needs.
I believe that you know immediately after giving birth that your child is different somehow.
As they grow, you notice that some milestones are different from the ones that your other children had and you silently chide yourself for comparing them.
Slower with walking, not speaking, unusual behaviour, unusual reactions to noise or red food.
You live with it every day and it becomes normal behaviour to you and your family, you adapt to the child’s needs and try to help them make sense of all that their jumbled up senses bring them.
Kids computing – there’s a lot of talk going on about it right now. What do you learn about computing in your school? Are they teaching you how to make cool video games? How to come up with a story that makes sense, how to make sure that it’s engaging, that there are challenges at each level, and that there’s a reward at the end? How to build that?
How to make the bird you toss flop realistically into a pile of whatever you choose – making sure that gravity works the way you would expect it to (or not). How to craft the graphics you need to tell your story? How to publish that to your own smartphone and to share it (or sell it!) to friends and strangers?
Hmmm, I didn’t think so. “ I’d rather just do some Power Point and Word exercises, “ said no kid, ever.
