There are 2 kinds of radiation, EM radiation (light, radio microwave, gamma) and particle radiation (alpha and beta)
Now, when someone is talking about radiation, they usually mean radiation from a discrete source, say, that lump of depleted uranium, or the radar tower over there, or the sun. BAckground radiation can change form place to place, so in washington DC, for example, there is a higher than usual incidence of radon gas, Radon gas is formed by other radioactive materials in the ground breaking up. the net result is a slight increase in alpha and beta radiation. So you need to measure this background radiation before you start a physics experement.
anyway. Alpha radiation is a free proton (possibly coupled to a neutron?) traveling at extreme velcocity, its not verry powerfull though - you could block it with a sheet of paper. IF it striked a molecule, It can excite a chemical reacion, So it could, concivable alter DNA< or something.
Beta ratiation is a free electron, traveling rather faster than the alpha particle was. Its quite energetic, and can penetrate metals to a depth of several mm. again, it can cause chemical reactions. Both of these forms of radiation are particle radiation, effectivley chunks of a radiactive atom that were spit off when it decomposed.
Gamma radiation accounts for much of the missing mass in a nuclear reaction, IT is extremely enerjetic, and will penetrate lead to a distance of some kilomiters. Again it can triger chemical reactions, but because it isn a charged particle, just an extremely high frequency, High energy EM photon basically, it will cook something if it actually interacts with it.
Any phsycics lab or chemistry lab that does experements with gieger coiunter will measure the background radiation juts before starting thier experement, because they need ot subtract the background radiation from the radiation measured during the experement, to find the radiation given off by the sample.
I doubt they keep a plot of radiation over time. However, some survey maps will have radiation counts plotted, becuase of radon gas, which is a common problem in north america. |
