Essay On LASER AND ITS MAGIC
Definition
Laser stands for fight amplification by stimulated emission of radiation. It stands for a device that produces a thin, intense beam of light. This light can burn a hole in a diamond or carry, the signals of many different television pictures at the same time. It has revolutionlised its use in medicine, scientific research, communication, industry and military operations.
Salient Features of Laser
There are four characteristics distinguishing laser from the light of an electric bulb, a fluorescent lamp or sun. The light of these bulbs or lamps travels in all directions. But as regards laser light, it is directional. It travels only in one direction, in a narrow parallel beam. It is coherent. The light waves are all ‘in step’ with one another. It means that laser light has one frequency. It has only one colour in place of seven colours. It is very bright. Its brightness can damage the looking eyes. The laser beam cutting a sheet metal can be increased to one million watts per square centimetre.
Uses of Laser Light
Laser light has many uses. Industrial lasers cut teeth in saws, drill eyes in surgical needles. A laser beam can be used to melt or cut hard materials. In communication, a laser is used to transmit voice messages and television signals. Being operated at a high frequency. Laser can carry much more information than radio waves. It can transmit many telephone calls and T.V. programmes at the same time, without any interference.
Scientific uses of Laser
Scientists use laser in scientific research to separate isotopes of uranium. These isotopes are essential for processing uranium as a fuel for nuclear reactors. Lasers can identify a criminal’s finger prints left on objects after forty years. In recent years laser surgery is regarded a successful process. The laser beam is pure energy, so it sterilises and seals blood vessels as it goes. Lasers can operate internally without cutting open the skin and muscle. It can be easily understood with example-supposing that a patient has an ulcer or a tumour, the doctor will insert into the patient an instrument called a ‘flexible fibre scope’ to verify his doubt. The flexible fibre scope is a special form of laser which enables light to travel round bends so that the surgeon can inspect the inside of patient’s stomach without cutting. If there is any wrong inside the stomach, the diseased body tissue can be burnt away to increase the intensity of the laser light.
Comprehensive Uses of Laser
The laser is immensely valuable in eye surgery. Retina welding can be done to make laser light shine at the patient’s eye. The heat of the laser beam welds the retina back into place. At present we are using laser to unblock arteries, to reconnect severed nerves, to remove warts, to remove birth marks and to treat bleeding ulcers. In addition to this, laser beams are used to guide bombs and artillery shells to their targets in military operations.
Vocabulary
Stimulated- excited, Intense- great, तीव्र | Emission- act of issuing, उत्सर्जन Consist- make of, Enormous- huge, Communication- sending messages संचार। Spectrum- band of seven colours, वर्णक्रम । Attempt- try प्रयत्न करना Missile- मिसाइल प्रक्षेपास्त्र ।
IMPORTANT LINK
- आदर्श इतिहास शिक्षक के गुण एंव समाज में भूमिका
- विभिन्न स्तरों पर इतिहास शिक्षण के उद्देश्य प्राथमिक, माध्यमिक तथा उच्चतर माध्यमिक स्तर
- इतिहास शिक्षण के उद्देश्य | माध्यमिक स्तर पर इतिहास शिक्षण के उद्देश्य | इतिहास शिक्षण के व्यवहारात्मक लाभ
- इतिहास शिक्षण में सहसम्बन्ध का क्या अर्थ है ? आप इतिहास शिक्षण का सह-सम्बन्ध अन्य विषयों से किस प्रकार स्थापित करेंगे ?
- इतिहास क्या है ? इतिहास की प्रकृति एवं क्षेत्र
- राष्ट्रीय उच्चतर शिक्षा अभियान के विषय में आप क्या जानते हैं ?
- शिक्षा के वैकल्पिक प्रयोग के सन्दर्भ में एस० एन० डी० टी० की भूमिका
- राष्ट्रीय पाठ्यचर्या की रूपरेखा (एन.सी.एफ.-2005) [National Curriculum Framework (NCF-2005) ]
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