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Saturday, June 28, 2008

Why is it better to eat at set times?

The process of digesting food takes a certain amount of time. It makes sense to eat at set times, leaving a sufficient amount of time between each meal for the stomach to digest the food. The Stomach juices have to break down the food, so that it can be absorbed by the body.
Naturally, the times and sizes of meals vary from society to society, and habits and customs tend to decide these.


Thursday, June 26, 2008

What alphabet is used by deaf People?

Understanding what somebody else is saying when you are deaf can be an impossible task, making the deaf person feel isolated and alone. Dumb people, unable to speak, are similarly denied the basic human medium of communication. Finger spelling is a method of talking to someone using a signaling code, similar to semaphore. The two-handed method used in Australia. Britain, Burma, India and some other countries, utilizes relative positions of the hands and fingers to spell different letters. It is quicker to learn than the one-handed method and can be seen more clearly at a distance.


Saturday, June 14, 2008

Is there life on other planets?

Ever since man has been aware of worlds beyond our own, he has begun to wonder whether he is alone in the Universe. Do other races of creatures very different or perhaps quite similar to ourselves exist on distant planets? This desire to explore beyond the confines of our world and to imagine what possible life forms could exist on other planets has let science fiction writers to describe all kinds of strange creatures. In the first men on the Moon, H. G.Wells tells of a species living in the craters and caves of the Moon that he calls the Selenties. These creatures resemble giant, intelligent ants. Of course, we are aware today that no such creatures exist and there never has been any form of life on the Moon, least of all the ‘Man in the Moon’. There have been other creatures from the Pages of science fiction such as the Mekons with tiny green bodies and huge heads whom Dan Dare met in his space travels in the Eagle comic. More recently, television has brought the terrifying, war-like Daleks who confronted Doctor Who in the programmed of the same name.
These are just a few of the imaginary men from outer space, but what are the possibilities of actual life forms? The first point to make is that there is little to be gained from trying to picture weird and wonderful creatures sprouting radio antennae from their heads and breathing liquid ammonia. We should try to confine ourselves to examining whether or not there is any chance of living systems much like our own somewhere else in the universe. It must also be remembered, however, that a living world elsewhere could be more or less developed than our own. In other words it could still be at the stage of a ‘primordial soup’ of primitive life forms or thousand of years more advanced than our own world.
Scientists have attempted to calculate how many galaxies there are in the Universe and how many solar systems are contained within these galaxies in a effort to work out how many planets there might be similar to our own. Even the most cautious would probably agree the number of planets in the Universe similar to our own probably runs into the thousands. This means that the chances are heavily in favour of there being many other worlds just like our own in which there are plants and animals and humans breathing air made of oxygen, nitrogen, carbon dioxide, and a few others gases.
Are these intelligent creatures trying to make contact with us using radio waves? Some people think so, but of course, they may be thousands of light years away so that by the time we received any message, they could be extinct. The possibility exists that we have already been visited by spacemen and that such wonders of the world as the Pyramids of Egypt were constructed with their help. Perhaps soon we shall know more of the creatures from outer space.


Thursday, June 12, 2008

How is man exploring outer space?

From earliest times men have dreamed of traveling in space, exploring new worlds, reaching for the stars – an apparently impossible dream. Then rocket research which took place during World War II gave a great impetus to space travel for which rocket propulsion is essential. After many experiments the first major break-through came in April 1961 when a Russian, Yuri Gagarin, spent 108 breath-taking minutes in space. Three weeks later Commander Alan Shephard of the U.S. Navy also journeyed into out space. The greatest milestone so far passed was in July 1969 when two more Americans, Neil Armstrong and Edwin J. Aldrin Jr. stepped on to the moon.


Monday, June 9, 2008

Why do we keep food in a fridge?

Food goes bad because bacteria, mould and microbes attack it. This happens more quickly in warm temperature, where as cold interrupts and even stops this process. So food will keep fresh for longer in a fridge.
Nowadays, there are enormous refrigerated rooms, fro string meat and vegetables which can then be eaten in perfectly good condition at any time of year. The technique of keeping foods refrigerated is most important in transporting fish from the sea to the markets where they are sold.


Tuesday, June 3, 2008

Why do people look so big on a film screen?

When we pass light through a film on to a screen a little distance away, we obtain a picture which is larger than the film itself. This is because there is a magnifying lens at the ends of the projector. The size of the image depends on the distance between the projector and the screen, and on the focusing power at the end of the projector. Projectors also have a system of lenses which help to make the picture clearer and sharper.