THE RAYS PRODUCED IN A CATHODE TUBE ARE FREE
THE RAYS PRODUCED IN A CATHODE TUBE ARE WINDOWS

Early alchemists experimented with many raw materials to discover many things we take for granted these days. When you go back just a couple of hundred years it was hard to separate science from magic. We would have no CRT display televisions, computer monitors or other display technologies such as liquid crystal display (LCD), and most certainly we wouldn’t have invented the smartphone screen you are probably reading this piece through! Cathode ray tubes: The alchemy of glass and metal If glass didn’t exist, we wouldn’t have been able to develop cathode ray tubes.

THE RAYS PRODUCED IN A CATHODE TUBE ARE WINDOWS

Without glass, we would never have windows in our homes to let in light or have created beautiful glassware to drink from and to decorate our homes with. The one ancient technology that we need to be so grateful for is the development of glass. Later we used bronze and then iron tools, eventually evolving to transform iron into steel and seeing the birth of the industrial revolution. Our ability to manipulate raw materials to suit our needs started in ancient history with the fashioning of rocks to make spears and arrowheads. The department and its current research – from dark matter detection to galaxy evolution to ultra-cold atomic physics – owe a lot to Thomson’s discovery of the electron 122 years ago.We have to credit the discovery of glass for giving us many useful things. In 1974, the physics department moved out to West Cambridge and by 2022, construction of the Cavendish III will be complete. The Cavendish Laboratory is still a key centre of physics research.

THE RAYS PRODUCED IN A CATHODE TUBE ARE FREE

This setting, within the Cavendish Laboratory on Free School Lane, was also the birthplace of Watson and Crick’s model of the helical structure of DNA. These approaches to understanding life and the universe at the smallest scale, were also applied to biological and chemical processes. Studying smaller phenomena, probing the very nature of life itself, required bigger apparatuses. These investigations often moved from table top experiments within the original Cavendish Laboratory, to bigger and bigger machines. By the 1920s, many scientists were studying electrons as part of the new discipline of quantum physics. The Cavendish Laboratory became an international scientific centre, attracting graduate students from across Britain and the world. This discovery was just one of the exciting developments in Cambridge physics around the turn of the nineteenth century, as physicists turned to probing the very state of matter. In this way, the announcement of the discovery was the icing on top of a giant cake of collaborative and cumulative work! The science behind this announcement began long before April 1897, and Thomson had been using a variety of instruments to investigate phenomena such as ‘cathode rays’. However, Thomson recognised the importance of this phenomenon as a constituent of matter, and identified a way in which the electron could be manipulated and experimented upon. This discovery led to the ‘plum pudding’ model of the atom which viewed the fundamental building blocks of matter as negatively charged corpuscles scattered throughout a cloud of positive charge.

He found that their mass to charge ratio was 1000 times smaller than the hydrogen ion – and called these new particles ‘corpuscles’. It was known that these rays could be deflected by a magnetic field, and Thomson used this property to investigate whether these rays were negatively charged particles. These rays caused fluorescence when they hit the far wall of the tube. He investigated the conduction of electricity through gases – work for which he would win a Nobel Prize in 1906.įor the 1897 experiment, Thomson used an electric discharge tube which produced ‘cathode rays’ at low pressures. In the Cavendish Laboratory, then located on Free School Lane, Thompson conducted experiments as Director of the Laboratory. Thomson announced his discovery of negatively charged constituents of the atom, which we now call electrons. Another one of these spots is located just outside the SPS Library on Free School Lane: the laboratory where the electron was discovered.ġ22 years ago, on the 30th of April 1897, J.

Perhaps the pub where Watson and Crick ‘discovered’ DNA or the Mathematical Bridge, supposedly ‘designed by Isaac Newton’.

Whenever you walk through central Cambridge, you will encounter tour groups gathering at key spots throughout the city centre.

The rays produced in a cathode tube are