Mössbauer effect

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Recoilless emission and recoilless absorption of gamma photons is called Mossbauer effect. It provides us a technique for producing and studying gamma rays whose energies are extremely well defined. Mossbauer effect was discovered by Rudolf Mossbauer in 1958. This effect is applied in the experimental field by the name Mossbauer spectroscopy. Let us first understand why a  nuclear transitions  occurs. After a radioactive nucleus undergoes decay (alpha decay, beta decay, k-capture) it many times reaches to the daughter nuclei state but contains too much energy to be in a final stable state. Unlike our electrons orbiting the nucleus, the nucleus itself doesn’t really have such orbits which are easy to visualize. So, let us just imagine it having a particular quantized energy. Now, to be in a stable ground state it must lose this extra energy. It does this by emitting gamma radiation of that energy. This is the process of nuclear transition, where the nucleus transitions from one
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Illusion created while standing in front of the mirror.

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I was recently faced by this confusing question, why do mirrors reverse left and right but not up and down? Interesting isn't it? but actually it is framed wrong because the mirrors do not reverse anything they just reflect back whatever is pointed to them.
Let's take the example of the image in this post. The baby has raised its one arm. If the mirror would have reversed left and right side then the arm other than this would have been seen as raised. But it doesn't happen that way because the function of the mirror is to reflect not to reverse. Now let's make it a bit simpler. Suppose you and your friend are holding a blue paper in your right hands. If your friend would be holding it in the right hand while standing in front of you then it is said that your friend has reversed the direction in which you are holding the paper. But instead of your friend, a mirror is kept in front of you then you would be seen to be holding the paper in the same direction because the mirror is actually reflecting and not reversing and reflection happens in the same direction in the same way[unless you do some trick and keep something more between you and the plane mirror(also when the mirror is not a plane one)].
Then why does it seem like the mirror is reversing? That's because our body is symmetrical. This symmetry creates a kind of illusion in front of our eyes and we perceive that the mirror is reversing instead of reflecting our image. If you write the word 'ASTRONOMY' on a big paper and place it in front of a plane mirror, you would feel as if it is reversed but try reading it from right-hand side. See? You no more feel that it is reversed. The reason for this case is that we mostly read from left-side instead of right-side.
[If this explanation is difficult to comprehend without visual aid then watch the video of the PhysicsGirl on YouTube regarding this topic.]
So the answer to the question 'why do mirrors reverse left and right but not up and down?' is just so simple. Sometimes the illusions are hovering in front of us but we don't realize them maybe because we are too used to believing in things as they are. But remember what one of the greatest minds Albert Einstein said:
"The important thing is to not stop questioning".

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