Electromagnetic Spectrum

1. Definition

1.1. Each type of radiation is produced and detected in its own special way

1.1.1. New node

1.2. The wavelengths of electromagnetic waves range from extremely short for gamma rays to very long for radio waves

1.3. All electromagnetic waves are transverse waves that travels with the same speed in vacup

2. Microwaves

2.1. Are radio waves of very short wavelengths, they have wavelengths of a few centimetres

2.2. Produced by special electronic devices such as a klystron tube

2.3. Used for satellite communication, satellite television and mobile phone networks. Another common use of microwaves is the microwave oven

2.4. Uses: Microwave cooking, Radar communication

3. Ultra-violet radiation

3.1. Is the radiation beyond the violet end of the visible spectrum

3.2. The main source of Ultra-violet radiation is sunlight and it is this radiation which gives suntans

3.3. Over-exposure to ultra-violet radiation can cause skin cencer, and damage to retina

3.4. Ultra-violet radiation kills bacteria and viruses. It is therefore used to sterilise hospital operation rooms and surgical instuments

3.5. Ultra-violet radiation is also used to check for forgery

3.6. Uses: Sunbeds, Forgery detection, Sterilisation

4. X-ray

4.1. Are produced when high energy electrons lose energy after striking a metal target

4.2. Used as diagnostic tool in medicine and dentistry. Doctors and dentists can examine the condition of a person's bones or the roots of teeth using X-rays

4.3. X-rays can damage or destroy living tissues and organisms, therefore we must avoid unecessary exposure

4.4. X-rays are also used to examine the hidden flaws and cracks of metal parts

4.5. Uses: Medical/ dental inspections, Airport security

5. Gamma rays

5.1. Are electromagnetic waves emitted by radioactive nuclei. They are also released during nuclear reactions

5.2. They penetrate very deeply and cause serious damage when absorbed by living tissues

5.3. Used under controlled situations to kill cancer cells and sterilisation of hospital equipment

5.4. Uses: Treatment of cancer, sterilising equipment

6. Done by: Ricardo Budidharma (13) 5 Aes 2

7. Radio Waves

7.1. longest wavelengths in the electromagnetic spectrum

7.2. The wavelengths range from several hundred metres (long wave) to a few centimetres (ultra high frequency

7.3. Used in radio and television communication to transmit sound and pictures

7.4. Produced by oscillating electric currents in an antenna

7.5. Uses: Radio and television communication, Radio telescope

8. Infra-red radiation

8.1. All objects emit infra-red radiation. As an object gets hotter, the infra-red wavelength emitted gets shorter, At low temperatures, all the radiation is infra-red and cannot be seen by the human eye

8.2. When objects absorb infra-red radiation, they become hotter. This property of infra-red radiation is used to provide heat treatment

8.3. Infra-red radiation emitted from a patient's body enables doctors to diagnose cancerous growth and blocked blood circulation

8.3.1. Military uses include surveillance, night vision. Non-military uses include thermal efficiency analysis, remote temperature sensing

8.4. One popular use of infra-red radiation today is the remote control for various electrical appliances

9. Visible light

9.1. The most familiar form of electromagnetic waves, may be defined as that part of the electromagnetic spectrum that the human eye can detect

9.2. The various wavelengths of light are classified by colours. The colors in the visible light spectrum are Red, Orange, Yellow, Green, Blue, Indigo and Violet

9.3. Light in the form of laser light also has a wide variety of applications in medicine, engineering, and telecommunication. In industries, lasers are used to weld metals together.

9.4. Uses: Optical Fibres for medical uses and telecommunications, Laser for medical, industrial and surveying uses