Name: X射線是如何工作的？|為什麼太空是黑色的？| 宇宙是什麼？ (How do X-rays work? |Why is Space Black? | #aumsum)
Uploaded: 2021-01-14T08:11:01.000Z
Duration: 1 min 7 s
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They were accidentally discovered by a physicist named Wilhelm Röntgen.

As he did not know what they were, he named them ''X-rays''.

But if an object's density is more, then these rays get absorbed and don't pass.

Due to this property, X-rays are used to detect fractures, tumors, etc.

To detect a fracture, X-rays are passed through our body which then hit an X-ray detector or a photographic film.

Now, since our tissues are not dense enough.

Much of the X-rays pass through them and get detected by the film.

Thus casting a dark or grey shadow on the film.

But as the bones are much denser, the rays get absorbed and hence, the bones appear white on the film.

This allows doctors to have a look at the
structure of bones and thus, spot the fracture.