|MadSci Network: Physics|
Hi Sabry, It is very nice and interesting observation. I have no such a FAN, however I will try to imagine this situation. I think it should be illusion, indeed, the fringes are on the wall, and you see so.. If there was an iterference fringe on the FAN screen as you claimed, your idea could be right. This idea is that slits are formed as the arms move very fastly relative to the stationary grid. I think you should realize three experiments more. First experiment, you should put the FAN away from the wall,then you should try to observe the same thins. If you observe what you are talking about.. it will not an illusion... Second experiment, you should use the lighthouse not regular lamp, you put it in front of the FAN, then take an observation, after that you should put over the FAN directly, then take an observation.. so you should make observations as the light are in different places. Last experiment can be with a different FAN, whose arms should be in the different number from other. After these observations, we can say somethings.. However, your last idea is very interesting.. Best wishes,
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