'The world is my country, science is my religion.' - Christiaan Huygens, Dutch Physicist (1629-1695) Wonderful perspective: liberating, bold, passionate. Suggesting that science can be cognate with religion might seem dangerous but, I think, is only an admission/understanding that even the most rational humans are only human and therefore prone to the emotional influences that can lead to the irrational excesses of religion. At the same time, the passions that lead to excess are also what drive us to excel - intellect without emotion is impotent. Tension of opposites, contradictions and the need for balance...
By Karim Attia I was sat on a train, thoughts meandering, when one of them, bizarrely, developed into the concept for an anti-aircraft weapon. One of the problems with most anti-aircraft weapons is that, to be effective, they have to hit a very fast and manoeuvrable target and cause it enough physical damage that it can no longer operate effectively. My concept would allow a weapon to be effective without the need for actually hitting the target. I envisage a pretty standard delivery platform (seeking missile of Surface to Air, or Air to Air, type) that detonates/deploys within the vicinity of the target aircraft. The weapon element would be an Electro-Magnetic Pulse (EMP) to disable the electronics of the target aircraft. As aircraft, particularly military ones, become ever more reliant on electronics (fly-by-wire avionics, weapons systems, radar, communications, etc) they become ever more vulnerable to their destruction, or failure, making EMP ever more effective. Although ‘hardening’ against EMP is possible, it is not general practice, even in military hardware. The obvious problem is generating sufficiently powerful EMP from a weapon system that has to be small and light (EMP is an effect of nuclear detonations but can be replicated with chemical-based weapons). Indeed, until the ...
Tags: atoms, electrons, energy, light, perception, physics, Science, wavelength
I asked the question and got this answer: The inherent properties of a material determine whether it can transmit light or not. Normally when light hits something it excites the electrons within its atoms and these then de-excite giving out light of a certain wavelength, which relates to the colour we see. Atoms have levels like orbits, that the electrons have to be in. The electrons can only jump from orbit to orbit when they have enough energy. With transparent materials these levels are so far apart that light doesn't have enough energy to excite the electrons and so the light passes straight through without interacting with the material - and that's why we can see through glass and water! Jamie, Sciencenet.org.uk (July 2001)
Tags: biochemistry, metabolism, physics, Science
I asked the question and got this answer: The production of heat is the necessary result of any process as the laws of physics prohibit anything being 100% efficient. In the context of the human body chemical reactions turn one molecule into another, with the difference in energy between them being released as heat. All animals produce heat, but humans and the other mammals, as well as birds are very good at regulating how much heat they produce and insulating against losing too much. It is for this reason that they are called warm-blooded. Heat is produced in all living cells by metabolic reactions (the chemical reactions used by life) but especially by ones that use a lot of energy such as muscles. Jamie, Sciencenet.org.uk (July 2001)