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Electromagnetic Radiation
Electromagnetic (EM) radiation is the energy transmitted through space or a material medium in the form of electromagnetic waves. The frequency range of such waves is tremendous, and is shown by the electromagnetic spectrum. These waves include radio waves, microwaves, infrared waves, visible light waves, ultraviolet (UV) waves, X-rays, and gamma rays.
2,156 Questions
What is the connection between x-rays and radiation?
Radio waves, Microwaves, Infrared, Visible Light, Ultraviolet, X-Rays, Gamma Rays etc. are all Electromagnetic radiation, just at different frequencies.
In physics, radiation is any process by which energy travels from one body to another.
When most people hear radiation they think of ionising radiation, which is a radiation that is strong enough to ionize atoms.
X-Rays are both Electromagnetic radiation and ionising radiation, because of the later it is a health hazard.
http://en.wikipedia.org/wiki/Radiography
What happens when you increase electromagnetic wave?
Increasing the intensity of an electromagnetic wave will result in higher energy and amplitude of the wave, which can lead to increased potential for heating, radiation exposure, and potential health risks. Additionally, at very high intensities, electromagnetic waves can cause damage to living tissues and electronic devices.
Can be felt as heat from an incandescent light bulb?
Yes, incandescent light is produced directly by heating a filament so hot that it glows, in accordance with cavity radiation laws. The energy to heat the filament comes from the electricity passing through it.
What blood is available that will give you an accurate estimate radiation dose?
A complete blood count (CBC) with differential test can provide information on white blood cell counts, which can be used to estimate radiation dose in cases of acute radiation exposure. Specifically, lymphocyte depletion kinetics can be used to estimate radiation dose.
Neutrinos are neutral radiation particles. They are subatomic particles with no electric charge, making them electrically neutral. Neutrinos are produced in various nuclear reactions, such as those in the sun and in nuclear reactors.
High energy radiation from the sun (gamma, x-ray, and short wavelength ultraviolet) is intercepted by gas molecules in the thermosphere and upper mesosphere. Oxygen molecules (O2) can be broken apart into atomic oxygen (O).
O2 + hi energy radiation --> O + O
Atoms can also have electrons stripped thereby becoming positively charged atoms, or ions. These charged ions of the ionosphere can reflect radio waves allowing very long transmission, for example of AM radio broadcasts at night.
Very energetic charged particles from the sun (solar wind), when they interact with the ions of the ionosphere can release light in the form of the auroras.
These interactions in the upper atmosphere shield the Earth's surface from the damaging effects of high energy, short wavelength radiation. It is also responsible for the heating of the thermosphere.
Ozonosphere At altitudes between around 20 to 30 km in the stratosphere the remaining ultraviolet radiation is absorbed by oxygen molecules, breaking them apart.
O2 + UV --> O + O
But unlike in the ionosphere where the gas molecules and atoms are widely spread apart, the density of the gas in the stratosphere is sufficient to allow the freed oxygen atoms (O) to bond with oxygen molecules (O2) forming ozone (O3).
O + O2 --> O3
The ozone molecules will also absorb ultraviolet radiation and break apart into oxygen molecules and single oxygen atoms again.
O3 + UV --> O2 + O
The forming, breaking, forming, breakingä of ozone is part of the atmosphere's barrier against harmful ultraviolet radiation. The absorption of UV is also the reason that the stratosphere warms with altitude, rather than cooling with altitude like the troposphere.
Ozone loss Ground-based and satellite-based monitoring of ozone levels in the stratosphere has shown a steady decline, especially in the Antarctic. During the Antarctic spring every year, an "ozone hole" or area of greatly depleted ozone larger than the United States forms. A similar depletion is now recognized in the Arctic, though it is not yet as bad as in the Antarctic. Even in midlatitudes stratospheric ozone is declining by around 7% every 10 years.
Beginning in the 1970s researchers suspected and then confirmed that ozone was being destroyed by chlorine (Cl) atoms liberated from CFCs (chlorinated fluorocarbons) used as a refrigerant, as solvent for cleaning electronic circuit boards, and for making foam rubber. Each chlorine atom can decompose around 100,000 ozone molecules which would otherwise decompose via absorbing ultraviolet radiation. Therefore thee destruction of ozone by chlorine atoms leads to an increase in harmful ultraviolet radiation reaching the Earth's surface.
The chlorine atoms can stay in the atmosphere fro 40 to 100 years, so even if we were to completely stop manufacturing all CFCs today the ozone losses would persist for some time. Happily, the international community has acted together to create laws to phase out CFCs. Much less CFCs are being used now. The "ozone hole" should gradually heal.
Do x-rays have a higher or lower energy than gamma rays?
Gamma rays have higher energy than X-rays. Gamma rays are a type of electromagnetic radiation with the highest energy in the electromagnetic spectrum, while X-rays have lower energy and fall between ultraviolet and gamma rays on the spectrum.
How do the various kinds of em waves different from each other?
Electromagnetic waves differ in their wavelength, frequency, and energy. For example, radio waves have long wavelengths and low frequency, while gamma rays have short wavelengths and high frequency. The energy of the waves increases as you move from radio waves to gamma rays along the electromagnetic spectrum.
What electromagnetic spectrum are safe for humans?
Visible light, radio waves and microwaves are generally considered safe for humans as they have lower energy levels and do not cause harm to human tissue. However, exposure to ultraviolet (UV), X-rays, and gamma rays can be harmful as they have higher energy levels and can damage cells and tissues. It is important to limit exposure to these higher energy forms of electromagnetic radiation.
Which characteristic of a light wave must increase as the light wave passes from glass into air?
The wavelength of the light wave must increase as it passes from glass into air. This is because light travels faster in air than in glass, causing the wavelength to stretch out as the wave exits the denser medium.
best way to write above question is:
Work function = 6.08*10^-19J This is energy Min required to free one electron.
what max wavelength is requred to cause this event?
remember wavlength inversely proportional to energy of photon via planks constant h
hence E = hV but E = hc / (wavelength)
where
E = energy photon
V = frequency of photon
h = planks constant = 6.626068 × 10-34 m2 kg / s
now, because Min energy is proportional to max wavelength, which is related to frequency:
V = E/h = (6.08*10^-19J) / ( 6.626068 × 10-34 m2 kg / s)
= 9.176 * 10^14hz
now C = V*(wavelength)
so (wavelength) = (3*10^8m/s) / (9.176*10^14hz) =
= 3.27*10^-7 meters
between 0.7 and 300 micrometres is infra-red, but this is 0.327 micrometers!! This seems like a very large wavelength, and therefore low energy value.
When light reflects off a material with a different refractive index, there is a phase change if the light transitions from a lower to a higher refractive index material. In this case, as the light goes from n=1.38 to n=1.40, there would be a phase change of 180 degrees.
How is UV light related to the ozone layer?
The two issues are not directly connected. The thin layer referred to as the hole in the ozone layer is a natural event that has been happening for eons as is global warming and cooling.
The ozone hole only lasts for a short time over each pole due to a lack of sunlight hitting that portion of the atmosphere.
When heat energy travels through solid materials it is called?
conduction. This process involves the transfer of heat between particles in direct contact with each other within the solid material.
Feeling heat on your hands is an example of radiation?
Feeling heat on your hands from a fire or a hot object is mainly through conduction. Radiation is when heat is transferred through electromagnetic waves, such as feeling the warmth of the sun.
What part of the electromagnetic spectrum can pass through flesh but is absorbed by bones and teeth?
X-rays can pass through flesh but are absorbed by bones and teeth due to their higher density. This property makes X-rays useful for medical imaging to capture images of bones and teeth hidden beneath the soft tissues of the body.
Why is sound not part of the electromagnetic spectrum?
Sound is a mechanical wave that requires a medium, such as air or water, to propagate. Electromagnetic waves, on the other hand, do not require a medium and can travel through a vacuum. This fundamental difference in how they travel means that sound is not considered part of the electromagnetic spectrum.
Does Betelgeuse emit more or less infrared radiation than the sun?
It's luminosity is 90,000 - 150,000 times that of the Sun, so it's safe to assume that the total amount of infrared radiation will also be more.
Since its temperature is lower than that of the Sun, the percentage of infrared radiation should also be higher.
No, oxygen in the atmosphere is important, because animals and plants cannot photosynthesize in the dark.
Oxygen forming ozone is important because DNA is damaged by what ozone absorbs, so it allows organsims without ring DNA, the ability to process telomerase whole-body, or multiple copies of their DNA in each cell, to survive. But life could exist without it, in fact there are RNA-based cells above the ozone layer.
Violet, with a wavelenght between 380 and 450 nm, which is near the end of the visible light, next to the ultraviolet region.
Be careful because talk about "colors" is quite dangerous. Firstly, different cultures has different names for the same color. In addition to this, due to the fact that the electromagnetic spectra is continuous (i.e., there are infinite's wavelenghts) it is impossible to say exactly which wavelenght is the limit of the visible region and, consequently, which is the color associate to this wavelenght.
Usually (but it is a convention) it is said that visible region is between 380 and 750 nm.
Yes, gamma rays are a type of natural radiation that are generated by radioactive materials or processes such as nuclear fission. They have the shortest wavelength and highest frequency among electromagnetic waves, and can be emitted from sources like stars, supernovae, and radioactive decay.
What type of wave could measure 5 meters in length?
A wave with a length of 5 meters would typically be a water wave in the ocean or a seismic wave during an earthquake. This length would be too large for electromagnetic waves such as light or radio waves.
No, radiation does not rise. Radiation can travel in all directions from its source, with its behavior dependent on the type of radiation and the surrounding environment.
What is the controlled variable for an electromagnetic?
One variable that needs to be controlled is the number of coils of the electromagnet as the more coils the stronger the magnetic force, so the same number of coils should be used for each test.
What is Earths incoming ultraviolet radiation absorbed by?
Nitrogen, Oxygen (UV-C and more energetic), and Ozone (UV-B and more energetic)
