Mini Physics Usage of gamma rays in medical treatment Gamma rays are ionizing radiation which can kill living cells. They are used to treat malignant tumours in radiotherapy. For treatment deep within the body, high energy photons are sent to reach the target tumour without affecting the surrounding tissue. Though x-rays are also ionising radiation, because of the lower energy compared to …
Usage of x-rays in hospital use and engineering applications X-ray photographs are used for medical diagnosis Soft X-rays penetrate flesh more readily than they do bone, which makes X-ray ‘shadow’ photographs possible. In industry, X-ray photographs are used to check for flaws in welded metal joints.
Usage of ultra-violet in sunbeds, fluorescent tubes and sterilization UV radiation is energetic enough to ionize atoms and so can cause harm to living tissue. Under excessive exposure, it will cause sunburn and skin cancers. It is used benefically in the sterilization of water, by killing off harmful living organisms present in the water for potable uses. Paper money are …
Usage of light in optical fibres, in medical uses and telecommunications Endoscopes are used to get the images of hollow organs by sending a beam of light through optical fibres. In an endoscope there are two bundles of very narrow optical fibres. The illumination bundle carries the light to the object being studied, and the image bundle carries back reflected …
Usage of infra-red waves in household appliances, television controllers and intruder alarms Infra-red radiation is emitted or absorbed by every object. We feel warm under the sun as we absorb more IR radiation than we emit (gain internal energy). We feel cool in an air-conditioned room as we emit more IR radiation than we absorb (lose internal energy). IR radiation …
Usage of microwaves in satellite television and telephone Microwaves are used to carry telephone calls and television channels as digital signals from ground station to satellites and vice versa. They are used for communications because they pass through the atmosphere without significant attenuation and they can be directed in beams with much less diffraction than radio-waves. The micro-wave frequencies are …
Ultrasound is the sound with frequencies higher than 20,000 hertz. Use of ultrasound Ultrasound is used to clean street lights by immersing the lighting unit in a tank of water and using ultrasonic waves to dislodge the dust particles from the surface of the unit. It is also used to clean jewelry and intricate mechanical and electronic components and …