Radiation has a profound effect on matter. Particularly in forms where it has high energy. There are basically two kinds of radiation, and they are electromagnetic energy and particulate radiation. Low energy electromagnetic radiation isn't generally hazardous, as long as the field strengths are low. You wouldn't want to stand in front of a radar antenna when it's radiating, but we are swept by low power electromagnet energy all the time. Those so-called radio waves are everywhere. Light is this kind of energy, too, and it's not too bad. But at higher energies, electromagnetic radiation is a hazard. Particulate radiation is straight up a problem. We often refer to particulate and high energy electromagnetic radiation as ionizing radiation, and both kinds have the ability to do some damage. Jump in the ride, fasten your seatbelt and we'll take a cruise into the quantum mechanical hood to check it out. Pay attention to the scenery along the way so you'll be up to speed when we get there. Matter is composed of atoms. Atomic nuclei are tightly bound protons and neutrons (1H excepted) with electrons hanging out in the electron clouds around them. Also, there are chemical bonds between atoms in a lot of different kinds of matter. These bonds involve the borrowing and loaning of electrons (the so-called ionic bonds) or the sharing of electrons (the so-called covalent bonds). That's matter, and now we're going to see what happens when we shoot stuff at it. Incoming! If electromagnetic (EM) radiation of sufficient energy slices into matter, things happen - and they ain't good. A general term for this high energy EM radiation is gamma rays. Sometimes we include the "hard" X-rays, the highest energy X-rays, in this group. The radiation can interact with chemical bonds, particularly the lower energy covalent bonds, and break them. If those bonds were in living material, this could (and does) affect injury. And if the molecules whose bonds are being broken are DNA, genetic damage results. That kind of damage is very, very hard for living things to correct. Other cellular or tissue damage has a better chance of being repairable. That ionizing EM radiation can also kick electrons out of the electron cloud of individual atoms, thus directly ionizing them. This creates havoc in living material. It should be noted that the radiation has to give up some of its energy when it "hammers" atoms or molecular bonds, but this is high energy radiation. It can do a lot of damage. And it can penetrate, too. When lower energy radiation comes into contact with a substance, it can't do as much damage. Sunlight on skin can do damage through prolonged exposure, but it is primarily the ultraviolet (UV) light that poses a hazard. It's the skin that takes the hit, and not deep tissue. A bit of sun is actually good for you. Anyway, the stuff we're talking about is of much higher energy (higher frequency, shorter wavelength). Shielding against this kind of radiation takes dense material. Lead is good, and it is in common use because it is abundant, cheap and easy to fabricate. We could use heavier (more dense) material, but who can afford, say, iridium or osmium? So we've got penetrating ionizing electromagnetic radiation slamming into stuff. But there is an unpleasant "extra" that is possible, and it's almost magical. If EM radiation of sufficient energy (1.022 MeV or higher) swings by an atomic nucleus, a chunk of its energy can be converted into matter. You're gonna love this. The phenomenon is called pair production, and both an electron and a positron (an anti-electron - antimatter!) are created out of pure electromagnetic energy! They come flying away from the event, and they can do some damage by ionizing stuff. The two particles represent (no big surprise) particulate radiation. The electron and positron created in pair production will ionize nearby atoms (affecting chemical bonding if there is any). They will do this as they give up energy and slow down in what are called scattering events. And the piece de resistance is that at some point the positron will come into contact with an electron, and the two will mutually annihilate each other. The result will be a pair of high energy electromagnetic rays. And we're back where we started with this pair of what are called gamma rays slicing through stuff and causing more disruption of atomic and molecular structures. Bad news? You ain't seen nothin' yet. Particulate radiation is particularly nasty. It does not, in general, have the penetrating power of electromagnetic ionizing radiation, but let's check it out. Electrons, protons and neutrons, the building blocks of matter, can become ionizing radiation. We've glimpsed the electron in action. It has a small mass, and even an energetic one can be stopped by a sheet of aluminum foil. Protons are over 1800 times more massive. They can do some serious damage, too. The neutron is a different story. You remember that it has no charge, so this bad boy has some serious penetrating power. It takes atomic nuclei to slow (scatter) and stop this guy, and hydrogen is particularly good at it. Friendly hydrogen has a nucleus that is just a proton, and hydrogen is abundant in water. Plastic, too. Oh, what about combinations of these particles? The helium nucleus is usually composed of a pair of protons and a pair of neutrons. When this particle is released as radiation, we call it an alpha particle. It doesn't travel far in air, and a sheet of paper will block it, but it does some heavy ionizing when it gets loose. It is a hazard when any radioactive material that decays by alpha emission get airborne and we inhale it. Now we have a radioactive source inside us. It doesn't get much worse. The alpha particle, the proton, the neutron, the electron and the positron are all products of radioactive decay. Different types of radioactive decay generate each of the "flavors" of particulate radiation, naturally. We've touched on all the basics here, probably. And we've leaned toward biochemical "matter" when we talked about interaction. We could have delved into, say, the damage caused to the steel of a nuclear reactor vessel by the neutron bombardment it takes during its lifetime, but we wanted to roll the areas to just cover basics. Hope we did it adequately.
Radiation is a form of heat transfer that does not require matter as a medium. Energy is transferred through electromagnetic waves, such as from the sun to the Earth.
The transfer of energy that does not require matter is called radiation. Radiation can propagate through empty space, such as in the form of electromagnetic waves like light or heat.
Radiation is the type of heat transfer that does not require matter. In radiation, energy is transferred in the form of electromagnetic waves, such as light and infrared radiation, through empty space. This allows heat to be transferred from the Sun to the Earth, for example.
True. Transfer of thermal energy by radiation does not require matter because it occurs through electromagnetic waves, such as infrared radiation, which can travel through vacuum where there is no matter. This form of energy transfer is how heat from the sun reaches Earth.
Electromagnetic radiation, such as light, does not require matter for traveling through space. It can propagate through a vacuum because it consists of waves of electric and magnetic fields.
Radiation does not require matter.
Radiation is a form of heat transfer that does not require matter as a medium. Energy is transferred through electromagnetic waves, such as from the sun to the Earth.
The transfer of energy that does not require matter is called radiation. Radiation can propagate through empty space, such as in the form of electromagnetic waves like light or heat.
Radiation, or electromagnetic waves do not require matter to carry energy.
Radiation is the type of heat transfer that does not require matter. In radiation, energy is transferred in the form of electromagnetic waves, such as light and infrared radiation, through empty space. This allows heat to be transferred from the Sun to the Earth, for example.
no it doesn't, only conduction and convection
True. Transfer of thermal energy by radiation does not require matter because it occurs through electromagnetic waves, such as infrared radiation, which can travel through vacuum where there is no matter. This form of energy transfer is how heat from the sun reaches Earth.
Electromagnetic radiation, such as light, does not require matter for traveling through space. It can propagate through a vacuum because it consists of waves of electric and magnetic fields.
Radiation
Radiation is the form of thermal transfer that does not require matter. It occurs through electromagnetic waves, such as light or infrared radiation, traveling through space and transferring heat energy. This process can happen even in a vacuum where there is no physical medium for heat transfer.
Conduction and convection use matter (such as solids, liquids, or gases) to transfer heat, while radiation does not require matter and can transfer heat through electromagnetic waves.
Now, this question has two answers. To give rise to, and to absorb, thermal radiation, matter is needed. Energy in the form of gravitational or electromagnetic fields neither emits nor absorbs thermal radiation. However, thermal radiation, an electromagnetic wave, does not need matter to transverse space.