An electromagnet is a magnet which is activated by the flow of electricity. This magnetism is temporary and can be switched off by removing the current. In fact, any wire with an electric current passing through it has a magnetic field surrounding it. This field is intensified by wrapping the coils around an iron core. …
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Fishing…
The school has an excellent stretch of the river Cherwell adjoining our fields and the North Oxford Angling Society, that runs our stretch of water, is very happy for us to fish there. It would not be game fishing (as there are relatively few trout on our stretch) but the earthier brand of angling known as coarse …
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Newton…
Newton, Isaac (1642–1727) was the English physicist and mathematician who laid the foundations of physics as a modern discipline. He discovered that white light is composed of many colours. He developed the three standard laws of motion. Unless acted upon by an unbalanced force, an object at rest stays at rest, and a moving object …
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Rubens Tube…
Some years ago I built a Rubens Tube out of a length of plastic guttering, and a speaker. The tube has holes drilled in it at regular intervals and a speaker fitted at one end. It is then flooded with methane from the lab supply and ignited. When music is played through the speaker the …
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Circuit Symbols…
Most of these should look familiar to you although relays & reed switches might be new. We will discuss them on another occasion. Make sure you can draw all of these symbols from memory. You are unlikely to need to draw a reed relay but you do need to be able to recognise one, and …
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EM Drive…
. NASA has recently announced that their research team has confirmed that the EM drive described above, when tested in a near vacuum, produced thrust. . The graph shows their raw data with error bars and the dotted line is their best fit line to show how the thrust in micro-newton (μN) is plotted against …
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Pluto…
I still think of Pluto as our ninth planet even though it was downgraded to dwarf planet status in 2006. It was only discovered in 1930 and since a year on Pluto is 248 years on Earth, it has not even completed one orbit of the Sun since its discovery. I include Pluto because I learned …
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Dark Matter and Dark Energy…
by Steve Z. Dark matter and dark energy are hypotheses to explain why the Universe is not behaving in the way we think it should be, suggesting that some other force is at work. In the 1990s we were quite certain of one thing about the Universe; it might have enough energy density to stop …
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Synlight…
I don’t suppose very many of my usual readers take The Guardian at home, but in general I have found its science reporting to be better than the other newspapers. They still fall prey to press releases from Universities and industry, publishing reports of scientific findings uncritically and without checking their sources, but usually I feel …
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Vera Rubin…
If you have read A Bloke In A Hat from 2014 then you will know the names of a few female scientists. Science has been dominated by men but I think that things have now improved such that nearly as many women as men apply to take science courses at University. One very great female scientist …
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