- #1
david2010
- 8
- 0
If an atom in a distant galaxy emits a uv photon, the photon would have had enough energy to cause photoelectric emission from a negatively charged zinc plate. By the time the photon reaches me on Earth it has been sufficiently 'redshifted' so that it could not cause photoelectric emission if it hit a negatively charged zinc plate. Where, in simple terms, has the missing energy gone or, where is the flaw in the question?