149. 2022年11月09日 15:02:23 : aG9dT8Ti22 : S3NTMGcyTXZmZ3M=[1]
Tube and Speed of Light (クリ)
Light of constant wavelength is passing through a tube (from left to right). Imagine that this tube is in motion to the left or the right. Frequency at the front end A and rear end B of the tube are the same always. Therefore, number of waves (it is invariant) existing in the tube is constant. So, wavelength does not vary. On the other hand, depending on the motion of the tube, the frequency at A and B varies. It is c and f that vary in the formula c = f λ.
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