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Light and gamma rays

  1. Aug 28, 2011 #1
    Hi everybody,
    We know that light is an electromagnetic wave.gamma rays are e.m.waves. Both of them have the same speed 3*10^8 m/s. Gamma ray have the property to penetrate in materials like wood,cement wall etc. But,light is not penetrating even in a single wood. What is the reason behind this.By,correlating the properties of gamma ray and light please give me answer...
  2. jcsd
  3. Aug 28, 2011 #2


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    The high energy of gamma rays give them enormous penetrating power.
  4. Aug 29, 2011 #3
    Thank you so much..
  5. Aug 29, 2011 #4


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    jigarbageha, Penetration depends on the properties of the substance. Light interacts with matter because its frequency is close to the natural frequencies of the atoms and molecules that make up the matter. Even for substances which look to us to be transparent, an interaction takes place causing an index of refraction for the light.

    X-rays and gamma rays have better penetration because their higher frequency means less interaction with the matter. They still do interact, however.
  6. Aug 29, 2011 #5


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    Hi energy and very short wave length. In a sense, the short wave lengths help gamma rays get through very small gaps between atoms.
  7. Aug 29, 2011 #6


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    There aren't really any gaps between atoms. Not in general. Metals are completely continuous, as far as electron densities go. It's about interaction cross-section, not whether or not there is an actual overlap.
  8. Aug 29, 2011 #7
    Thanks a lot...
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