I have never really written much about pressure on the blog. Perhaps it has always seemed a little dull but questions do come up about pressure so I ought to have a go. It ties in nicely with the posts about forces because pressure is force applied per square centimetre. At C.E. pressure will always …
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Category:Physics
Units and Calculations…
There are not a great many types of calculation you will be asked to do at this level. You may be asked about speed, density, pressure or perhaps calculating weight from mass and the force of gravity. The question will usually give you enough information for you to work out what sums you need to …
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The Hills Are Alive With…
Sound travels as waves at about 340 m/s in air and if you can’t remember some of the terminology about waves you might look here at a previous post. You could also look at this excellent page to play with an animation exploring amplitude, frequency and wavelength. (Don’t forget that you can also use the …
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Gold Part Two…
[This is follow up to Gold Part One.] A pupil asked… Will the earth naturally produce more gold for us to extract? How long will this take? How long is the half-life of gold and what does it decompose into? Would it be possible to industrially produce gold from different atoms? A. Pupil Esq. When …
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Nuclear Fusion…
At a laboratory in California, in what is called the National Ignition Facility, is the largest collection of giant lasers in the world. Their aim is to produce sustainable nuclear fusion similar to that happening in the Sun. The nuclear power stations we currently have split large atoms (such as Uranium) in a process called …
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Words, Words, Words (Phys. Ed.)…
Some physics words with links to relevant Twig World videos. You will need to be logged into your Twig World account to be able to view the videos but you only need to log in once then you should be fine. Force – a force is a push or a pull gravity/weight – the force …
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Raindrops Keep Falling…
In the rain, is it better to walk or run if you want to get the least wet possible? This is such an obvious sounding question. Surely you need to run to spend as little time in the rain as possible? It is not quite that simple although most physicists do agree that if it …
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Osmosis…
One of my favourite SF classroom moments was when discussing density. I said that osmium was the densest metal, and therefore the densest material that one would be likely to meet on Earth, at 22.59 g/cm3 (with iridium as a close second on 22.56 g/cm3). A voice chimed up from the front asking whether osmium …
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Phase Transition…
. The graph shows how the temperature (in this case of some ice) changes over time when left out on a laboratory bench at 20 °C. The ice changes from being in a solid state to a liquid state. This change of state is a phase transition. There are five distinct regions of the graph …
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The Dzhanibekov Effect…
Also known as the Tennis Racket Theorem. Or intermediate axis theorem. When a gyroscope spins it stays upright because the spinning weight at its core resists any attempts to knock it off its access. This is called rotational inertia. Inertia refers to the tendency for moving objects to remain moving or stationary ones to remain …
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