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Most of these waves are used in everyday life, waves such as X-rays are used to take pictures of peoples bones, visible light is used to see, infrared is used to heat objects, and is applied in ovens and Microwaves and Radio waves are used in things such as radios and microwave ovens. The only wave not commonly applied to everyday life is Gamma Rays, as they are damaging to living cells and can kill people.
Gamma Rays- Gamma Rays have the shortest wavelength and are the most damaging to living cells. They have the ability to pass through the human skin. Gamma Rays can damage cells and kill people, and are only used in experiments to split materials and look at them in more detail.

X-Rays- X rays have the second shortest wavelength and can be damaging to human cells over extended exposure. X-rays can be applied in real life to see inside the human body, and determine whether damage has been done. People cannot have too many x-rays in one year, as this may cause permanent damage to them, this is called radiation poisoning. A story about the dangers of radiation poisoning can be found here .

Ultraviolet- Ultraviolet has a short wavelength, but does not do as much damage as for example, X-rays. Ultraviolet light can come from the sun, too much exposure to ultraviolet light can result in burns, usually called "sunburns". Skin cancer can also occur. UV is also used in lasers, lamps and LEDS. UV is also a source of vitamin D with healthy exposure.
Visible Light- Visible light is where the Electromagnetic Spectrum starts to gain longer wavelengths. Visible light is the only light in the electromagnetic spectrum that we can see, and has no harmful effects to living cells. Visible light can be seen in rainbows, headlights and even laptops!
Infrared- Infrared also has a long wavelength. Infrared mainly relates to heat, and is emitted by everything with temperature. Infrared has short infrared and long infrared, the former is closer to visible light, and can't be seen or felt. The latter is closer to microwave and radio waves. Infrared is applied by the military when they use infrared through night vision. Everything emits infrared, but humans emit a lot, and the infrared will pick it up. Short infrared is used in things such as television remotes.
Micro/radio Waves- Microwaves and Radiowaves are the shortest waves in the electromagnetic spectrum. Microwaves and Radiowaves are invisible to the human eye. They can be used in things such as a microwave oven and a radio. These waves are used to communicate in everyday life through the radio system.
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E-M Trends
The Electromagnetic Spectrum has many trends that make it unique. One of these is the fact that the wavelengths get shorter from the right to the left of the spectrum. When these wavelengths get shorter, the corresponding electromagnetic wave gets more damaging. These trends can be seen in everyday life, with gamma rays damaging living cells when in contact with them, whilst on the other side of the spectrum, the microwaves or radiowaves are completely harmless.

Wavelength, energy and frequency trends
Wavelength, energy and frequency trends apply to the fact that all are related physically, and mathematically. Different waves can be described in different ways due to the way they emit their frequency, energy or wavelength. For example radio waves would usually be described with a frequency, as radio towers emit radio waves at different frequencies. X-rays would be described as energy, as they emit energy that can damage human cells. Finally, microwaves would be described with wavelength. This happens because it is easier to measure the parts of the spectrum in certain units. Frequency being hertz, wavelengths metres and energy, when describing light, as electron volts, or eV.
The light Spectrum and Trends
Light visible to the human eye is called white light. This light has a spectrum of 7 colours: Red, Orange, Yellow, Green, Blue, Indigo and violet. When white light hits an object, all light in the spectrum is absorbed, except for the colour that said object is. For example, if white light hits an apple, all light is absorbed except for red, and that is the colour picked up by the Eye. A fascinating phenomenon is that of dispersion. When a light hits a prism, all the colours of the spectrum are dispersed, and are clearly visible. This happens because light such as violet has a high frequency, and will therefore refract more, whilst a colour such as red will not refract as much, as it has a lower frequency.
The way the human eye detects light is through cone cells in the eye. See The Eye and Ear for more details. When, for example, red light is shone on a orange, no light would be reflected, as the orange would absorb red light.

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Dispersion- Science World 3



The Speed of Light
Light travels faster than any other known wave. It is faster than a mechanical wave as it does not need a medium to travel through, and therefore retains an average speed of about 300,000 metres per second, and is ten times faster than the speed of sound. This speed however, is not always the case, if light travels through water, it moves slower, as the particles are more dense in air then in water. This is known as refraction. The light barrier cannot be broken, unlike the sound barrier, which can be broken by some jets.

To see how some of this relates to real life, go to Real World Example Video!!!!!!!
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