Definition of backpack. 1a : a load carried on the backb : a camping pack (as of canvas or nylon) supported by a usually aluminum frame and carried on the backc : knapsack.
Three types of radioation-Alpha, Beta, Gamma. There are three primary types of radiation: 1  Alpha-these are fast moving helium atoms. 2  They have high energy, typically in the MeV range, but due to their large mass, they are stopped by just a few inches of air, or a piece of paper.3  Beta-these are fast moving electrons. Alpha-these are fast moving helium atoms. 2  They have high energy, typically in the MeV range, but due to their large mass, they are stopped by just a few inches of air, or a piece of paper. 3  Beta-these are fast moving electrons. 4  They typically have energies in the range of a few hundred keV to several MeV.
Radiation is the emission (sending out) of energy from any source. There are many types of radiation. Ultraviolet (UV) radiation is a form of electromagnetic radiation. The main source of UV radiation (rays) is the sun, although it can also come from man-made sources such as tanning beds and welding torches.Radiation exists across a spectrum from very high-energy (high-frequency) radiation â like x-rays and gamma rays â to very low-energy (low-frequency) radiation â like radio waves.UV rays have more energy than visible light, but not as much as x-rays.adiation exists across a spectrum from very high-energy (high-frequency) radiation â like x-rays and gamma rays â to very low-energy (low-frequency) radiation â like radio waves. UV rays have more energy than visible light, but not as much as x-rays.