December 11th, 2007
Pencils Tin
Gamma rays can be completely blocked by?
A. 1 sheet of paper
B. 1 cm cubed of tin foil.
C. 1 cm cubed of concrete.
D. 1 lead pencil.
E. none of the above
its E none of the above!
as:
Shielding for gamma rays requires large amounts of mass. The material used for shielding takes into account that gamma rays are better absorbed by materials with high atomic number and high density. Also, the higher the energy of the gamma rays, the thicker the shielding required. Materials for shielding gamma rays are typically illustrated by the thickness required to reduce the intensity of the gamma rays by one half (the half value layer or HVL). For example, gamma rays that require 1 cm (0.4 inches) of lead to reduce their intensity by 50% will also have their intensity reduced in half by 6 cm (2½ inches) of concrete or 9 cm (3½ inches) of packed dirt.
http://en.wikipedia.org/wiki/Gamma_rays
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Prismacolor Premier Colored Pencils. A pencil enthusiast's dream, artist-quality colored pencils are perfect for every level of expertise. High-grade pigments provide rich color saturation. Soft, thick core designed for superior blending and shading...
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Prismacolor Thick Lead 120 Count Tin Color Pencil Set - 03602
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Tags: art, bamboo_candles, bamboo_mobiles, butterflies, pencils
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