Essay on Electro: Radiation Electromagnetic Radiation

Submitted By amyian
Words: 1717
Pages: 7
Open Document
White light can be split up into a spectrum of many different colours and visible light is just part of a continuous spectrum of electromagnetic radiation. Different types of electromagnetic radiation have different hazards and uses.
What is a spectrum?
The visible spectrum a rainbow appears to come out of the prism
Using a prism, you can split up white light to form a spectrum. (A prism is a block of glass with a triangular cross-section.) The light waves are refracted as they enter and leave the prism. The shorter the wavelength of the light, the more it is refracted. As a result, red light is refracted the least and violet light is refracted the most, causing the coloured light to spread out to form a spectrum.
The electromagnetic spectrum
Visible light is just one type of electromagnetic radiation: there are various types of electromagnetic radiation with longer wavelengths of light than red light and with shorter wavelengths than violet light. All the different types of electromagnetic waves travel at the same speed through space.
The discovery of infrared

National Maritime Museum London UK
British astronomer William Herschel (1738-1822) was making observations of the sun when he put coloured filters over his telescope in order to make his observations safer. He noticed that different coloured filters heated up his telescope by different amounts. Using a prism to break up visible light he put a thermometer in the different colours. He found that the temperature rose as he moved the thermometer from violet to red. He then measured the temperature where there was no visible light, at the red end of the spectrum. The temperature was the highest: he had discovered infrared.

The discovery of ultraviolet
Following Herschel’s work, Johann Ritter (1776-1810) tried to find invisible rays at the violet end of the spectrum. As part of the experiment he used silver chloride, which turns black when exposed to light. This happened fastest when exposed to the invisible rays at the violet end of the spectrum.

The main types of electromagnetic radiation
X-rays, visible light and radio waves are all types of electromagnetic radiation.
The main types of electromagnetic radiation frequency type of electromagnetic radiation wavelength highest gamma radiation shortest X-rays

ultraviolet

visible light

infrared

microwaves

lowest radio waves longest All types of electromagnetic radiation: are transverse waves travel at the same speed in a vacuum - empty space.
The speed of electromagnetic radiation in a vacuum is 299,792,458 m/s. This is approximately three hundred million metres per second - nearly nine hundred thousand times faster than sound, which is why you see a flash of lightning before you hear the thunder.

Hazards of electromagnetic radiation
Over-exposure to certain types of electromagnetic radiation can be harmful. The higher the frequency of the radiation, the more damage it is likely to cause to the body: microwaves cause internal heating of body tissues infrared radiation is felt as heat and causes skin burns
X-rays damage cells, causing mutations (which may lead to cancer) and cell death gamma rays also damage cells, causing mutations (which may lead to cancer) and cell death.
Microwaves
Microwave radiation can be used to transmit signals such as those for mobile phone calls. Microwave transmitters and receivers on buildings and masts communicate with the mobile phones in their range.
Ultraviolet light
Ultraviolet radiation - UV - is found naturally in sunlight. We cannot see or feel ultraviolet radiation, but our skin responds to it by turning darker. This happens as our bodies attempt to reduce the amount of ultraviolet radiation reaching deeper skin tissues. Darker skins absorb more ultraviolet light, so less ultraviolet radiation reaches the deeper tissues. This is important, because ultraviolet radiation can cause normal cells to become cancerous.
The three main types of ultraviolet radiation, and some of
Show More

Related Documents: Essay on Electro: Radiation Electromagnetic Radiation

Brain Tumors

phones and our bodies is healthy? The opponents base their concern on life experiences of family members that die or have had cancer because of the long period of mobile use. The Word Health Organization in 2011 classified the cell phones low-energy radiation emission as being “possibly carcinogenic” because of the link between cell phone use and a type of malignant brain tumor called glioma and a benign brain tumor called acoustic neuroma. The proponent argument is based on the case study led by epidemiologist…

Words 1491 - Pages 6

Essay about Math: Magnetic Field and Energy

decelerate - objects accelerate when there is a net force acting on it - objects moving at constant speeds do not have net force - objects at rest do not have net force Fundamental Forces - 4 Fundamental forces - Gravitational force - Electromagnetic force – electrons/protons attract/repel - Weak nuclear force - Strong nuclear force – holds nucleus of atoms together - Other everyday forces are one or more of these acting in a specific way Everyday Forces - Force of friction – always parallel…

Words 3040 - Pages 13

Essays: Double Positive Charge

atoms that are radio active * An individual radioactive isotope is known as a Radioisotope Artificial Transmutation – Creates artificial radioisotopes * Uses the process of neutron absorption Geiger Counter is used to measure and detect radiation Alpha Particles – (2p & 2n) Heavy and slow moving * Double positive charge * Emitted from the nucleus at less than 10% of the speed of light * Poor Penetrating ability * Travels only a few cm before losing energy Beta Particles…

Words 1240 - Pages 5

Essay on WiFi a Thalidomide in the making wh

been written for all students and non‐scientists to understand. 1 2013 Abstract As stated by University Researchers, Government Scientists and International Scientific Advisors; a minimum of 57.7% of schoolgirls exposed to low‐level microwave radiation (Wi‐fi) are at risk of suffering stillbirth, foetal abnormalities or genetically damaged children, when they give birth. Any genetic damage may pass to successive generations. 2 3 2013 2013…

Words 4476 - Pages 18

Assignment 2 Design Operation Essay

the current must be switched to the loops moving into position under the poles. This may be done with a ‘commutator’ and ‘brushes’ but it can be done electronically. The magnetic poles may be permanent magnets but in more powerful motors they are electro-magnets with coils wounds on the poles called ‘field windings’ The stator and rotor form a magnetic circuit and flux crosses the loops on the armature. The strength of the magnetic flux can be changed by changing the current. The rotor would be called…

Words 3433 - Pages 14

Highly Resonant Wireless Power Transfer: Safe, Efficient, And Over Distance

pioneering ideas and experiments perhaps being the most well-known early attempts to do so [1]. He had a vision of wirelessly distributing power over large distances using the earth’s ionosphere. Most approaches to wireless power transfer use an electromagnetic (EM) field of some frequency as the means by which the energy is sent. At the high frequency end of the spectrum are optical techniques that use lasers to send power via a collimated beam of light to a remote detector where the received photons…

Words 7561 - Pages 31

global warming Essay

01 - Global Warming & The Greenhouse Effect Small scale: What is a greenhouse? * A glass room that stays warm without artificial heat sources Types of light passing through Visible Light Ultra-Violet Light Infrared Light (makes skin hotter / tan) Trapped Infrared The little bit of IR that enters becomes trapped within the greenhouse This heats the interior of the space by 30* to 40* F Large scale: The Greenhouse Effect in the Atmosphere Diagram of the Earth * The Atmospheric Gasses…

Words 2664 - Pages 11

Exploration Of Using FBG Sensor For Axle Counter In Railway Engineering

refractive index grating is reported by Hill et al. in 1978 [2]. Subsequently, Meltz et al. devise a method to controll the fabrication of grating using UV laser [3]. Basically, when a germanium-doped silica core fibre is exposed to ultraviolet (UV) radiation (with wavelength around 240 nm), it produces a permanent change in the refractive index of the germanium-doped region, due to the photosensitivity nature of the fibre and, using such an exposure, it is possible to obtain realize changes…

Words 3081 - Pages 13

What Causes Cancer Essay examples

What Causes Cancer? The past century has revealed extensive research implicating a microbial origin as the cause of cancer. At the leading edge, Dr. Royal Rife’s 1930s research identified evidence of a human cancer virus by isolating and culturing the suspected virus. After injecting numerous rats with the microbe, cancer consistently developed in both live cells and tissue cultures. Numerous other researchers also found evidence proving Rife’s findings. Currently, Canadian biologist Gaston…

Words 3947 - Pages 16

WORD ROOTS Essay

Word Roots- Chapter 2 an- = not (anion: a negatively charged ion) co- = together; -valent = strength (covalent bond: an attraction between atoms that share one or more pairs of outer-shell electrons) electro- = electricity (electronegativity: the tendency for an atom to pull electrons towards itself) iso- = equal (isotope: an element having the same number of protons and electrons but a different number of neutrons) neutr- = neither (neutron: a subatomic particle with a neutral electrical…

Words 8469 - Pages 34