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Electromagnetic waves or EM for short are waves that are found to be traveling electric field or magnetic fields. They are created as a result of vibrations that travel across these fields. These types of waves are formed when electronic and magnetic fields come into contact. The electric and magnetic fields are perpendicular to each other and to the direction of the electromagnetic waves.These waves travel in a vacuum that has a constant velocity of 3.00 x 108 ms-1. These waves can travel through anything from water to solid materials. These waves do not need a medium to allow them to travel. A medium is a substance or material that carries the wave.
EM waves are type of transverse waves. This means the waves oscillate along a path at a right angel to the direction where the waves will lead to. Also, transverse waves are measured by their height and wavelength which is the distance between the highest and lowest point s of two consecutive waves. Electromagnetic waves can be split in to a range of different frequencies and this is known to be the electromagnetic spectrum. All these waves have different wave lengths and frequencies but all travel at the same speed which is the speed of light. Radio wavesRadio waves are a type of wave that can be found on the electromagnetic spectrum. These waves have the longest wave length and lowest frequency. They are made with different transmitters that will vary depending on the wavelength. They are also mainly used for communication.
Other uses include:AM and FM radioCellular telephonesMicrowavesMicrowaves are a type of wave they can be found on the electromagnetic spectrum. They work by transmitting signals from the transmitters to the receivers. They travel in a vacuum at the speed of light. Their wavelengths range from one meter to one millimetre. Microwaves have many uses. They can be used to heat up substances by causing the water and fat molecules to vibrate. Mobile phones and WIFI use microwaves. Mobile phones use small antennas to generate the microwaves. As they are small mobile phone companies need to have many transmitter towers for them to work. Microwaves are also used in traffic speed cameras and radars that can be found on aircrafts, ships or used in weather forecasts. Infrared wavesInfrared light is emitted or absorbed by molecules when they change their rotational- vibrational movement. These are rotations or vibrations of molecules. These waves are just below visible red light on the electromagnetic spectrum. These waves have many different uses and can be found within remote controls, in heat lamps and short-range communications. They can also be used to see in the dark as all objects give of infrared waves.
Visible light is the portion of the electromagnetic spectrum that is visible to the human eye. The spectrum doesn’t contain all the colours that the human eye and brain can distinguish. These waves are produced by vibrations and rotations of atoms and molecules and by electronic transitions within atoms and molecules. Light waves are emitted by anything that’s hot enough to glow. This is the reason we see light from light bulbs. An electric current heat the lamp fibres which causes it to glow. Light waves can be used with the use of lazes. Lasers are used in disc and DVD players as the light is reflected from the disc and the pattern is detected and translated into sound or data.
Ultraviolet light is found in sunlight and is emitted by electric arcs and specialised lights. Electric arcs are visible plasms discharge that occur between two electrodes what is caused by electrical current ionising gasses in the air. This can sometimes result in chemical reactions occurring which can cause substances to glow or fluoresce. This type of radiation is not visible to the human eye but the effects of it on the skin are. Suntan and sunburn are the effects of darkened pigments caused by ultraviolet radiation. Ultraviolet waves are used for a range of different things. These include sun tan, detection of fraudulent bank notes and hardening some dental filings. They can also be found in clubs to make your clothes glow. This happens as substances in washing solutions glow when ultraviolet lights come into contact with them. This can also be used to kill microbes. In health care settings ultraviolet lamps are used to sterilise surgical equipment and to filter the air of operating theatres. They can also be used to stimulate vitamin D production as ultraviolet rays can help produce this.
X-rays are found on the electromagnetic spectrum. They have very high frequencies and can travel through most substances. X-rays can be emitted by the stars and can be through machines. X-ray machines are used in many health setting to see the inside of people. These work by firing a beam of electrons on the target area with soft tissue becoming black and hard tissue being shown as white. X-rays can show soft tissue if Barium rich meal is consumed beforehand. This will be absorbed by the x-rays and will allow an image to form. X-rays area also used within airports to check the content of your luggage.