Alpha particles penetrating ability

Alpha particles are positively charged with a mass of 4 amu (atomic mass units, 1amu=1/12th.of carbon atom). They are, then, the nuclei of Helium atoms. These particles are the slowest moving and the most massive of the three types of radioactivity. As such, they have the least penetrating ability through matter. A sheet of paper will stop their movement. 

This radiation release often accompanies the release of alpha or beta particles because of the high energy arrangement left in the nucleus after the release of alpha or beta particles. Gamma radiation has the greatest penetrating ability. Concrete, 6 inches thick, is needed to stop gamma radiation. 

Alpha decay improves the stability of radioactive nuclei that lie to the right of the belt of stability. Emission of an alpha particle moves the nucleus diagonally toward the belt of stability because the numbers of both protons and neutrons are decreased by 2. The alpha particle is the least dangerous form of radiation as it has little ability to penetrate tissue. 

Notice that the atomic number in the equation decreases by two while the mass number decreases by four. Alpha particles have very low penetrating ability because they are large and soon collide with other matter. Exposure to external sources of alpha radiation is usually harmless. However, if substances that undergo alpha decay are ingested or inhaled, the radiation can be quite damaging to the body s internal organs. 

The penetrating abilities of the particles and rays are proportional to their energies. Beta particles and positrons are about 100 times more penetrating than the heavier and slower-moving alpha particles. They can be stopped by a g-inch-thick (0.3 cm) aluminum... 

Objective 23 116. Describe the relative penetrating ability of alpha particles, beta particles, and... 

When alpha particles collide with matter, they generate a large number of ions and therefore can damage biological molecirles. The ability of radiation to create ions in matter is called ianiziiig power. However, because of their relatively large size, alpha particles have low penetrating power they do not get very far in air... 

The effect of radiation at the cellular level is dependent, of eourse, on the ability of the photon or particle to penetrate proteetive layers of clothing (in humans) and the skin. Alpha particles have very low... 

How does the penetrating ability of gamma rays compare with that of alpha particles and beta particles ... 

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