What is the Physical Reason for Gamma Rays Being Absorbed?

In summary, gamma rays have higher penetration than infrared rays, but x-rays have higher frequency and can penetrate through skin/body.
  • #1
jaydnul
558
15
But high frequency are absorbed, like gamma rays. I would think it would be the opposite. So what's the physical reason?
 
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  • #2


Why is it that lower frequency EM waves are aloud to pass through objects, but high frequency are absorbed, like gamma rays. I would think it would be the opposite. So what's the physical reason?
I believe you'll find that gamma rays have higher penetration in, say, steel, than infrared rays.
I can stop a lot of visible light with a black sheet of paper - but this has almost no effect on high energy gammas.

Where did you get this idea from?
 
  • #3


This does not seem right even if one invokes the concept of plasma frequency.Metals having plasma frequency higher than frequency of light will reflect it otherwise transmit.May be you can see feynman lectures vol. 2 ,last 1/4 part for it.
 
  • #4


Radio waves (low f) pass through walls that visible light doesn't. But x-rays (high f) also pass through things visible light doesn't. So frequency isn't the determining factor here perhaps?
 
  • #5


lundyjb said:
But high frequency are absorbed, like gamma rays. I would think it would be the opposite. So what's the physical reason?

But x-rays, which has a higher frequency than visible light, can penetrate through your skin/body, while visible light can't!

So now we have a contradiction to your assertion, which is something that you should have brought up (I'm assuming you are well-familiar with x-rays). So now how would you proceed in your thinking? Is this whole thing really an issue with EM wave, or is this really more of a function of the material that interacts with that EM wave? Remember, there are two parties involved here - the light and the material that it is impinging upon. You seem to have dismissed the latter.

Just because the bride wears all the fancy dress and gets all the attention doesn't mean that you can ignore the groom!

Zz.
 

FAQ: What is the Physical Reason for Gamma Rays Being Absorbed?

1. What is the physical reason for gamma rays being absorbed?

Gamma rays are absorbed due to the interaction between the high-energy photons and the electrons in the matter they pass through. This interaction causes the electrons to be excited to a higher energy state or even ejected from the atom, resulting in the absorption of the gamma ray.

2. How does the energy of gamma rays affect their absorption?

The higher the energy of the gamma ray, the more likely it is to interact with the electrons in the matter and be absorbed. This is because higher energy gamma rays have shorter wavelengths, making them more able to penetrate into the atomic structure and interact with the electrons.

3. What materials are most effective at absorbing gamma rays?

Dense materials with high atomic numbers, such as lead or uranium, are most effective at absorbing gamma rays. This is because they have a larger number of electrons that can interact with the gamma rays, resulting in a higher chance of absorption.

4. Why are gamma rays more easily absorbed than other forms of radiation?

Gamma rays are more easily absorbed due to their high energy and short wavelengths. This allows them to interact with the electrons in matter more readily, resulting in a higher chance of absorption compared to other forms of radiation such as X-rays or visible light.

5. Can the absorption of gamma rays be controlled?

Yes, the absorption of gamma rays can be controlled by using materials with different densities and atomic numbers. For example, medical imaging techniques use different materials to selectively absorb gamma rays and create an image. Additionally, the thickness of the material can also affect the absorption of gamma rays.

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