Light, photons, reflection and percentages

AI Thread Summary
The discussion centers on the behavior of light and photons when interacting with glass, particularly regarding reflection and transmission probabilities. It highlights that while a photon has a 95% chance of being reflected, this probability applies over a large number of trials, not individual instances. When only one or two photons interact with the glass, the outcomes can deviate from the expected percentages, leading to potential misconceptions about reflection rates. The conversation emphasizes the importance of sample size in accurately predicting outcomes in quantum events. Ultimately, as the number of photons increases, the observed reflection rate will align more closely with the theoretical 95%.
cyberstu
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Hey all, I am new to these forums. I am thinking of taking a distance learning degree in the near future from Open University in Physics, so decided to do some reading up first as it has been a while since I hav etuched physics.

Anyway I am reading a book at the minute "Quantam Theory cannot hurt you" by Marcus Chown, and it is discussing light and reflection. It is saying that if 95% percent of all light is reflected, however each photon has a 95% chance of passing thru a glass window a 5% chance of passing through. However what if only one or two light photons hit a glass window, surely if one photon hit it would be 100% refelected or passed through and if two photons hit it would be 50 50.

Thanks for any replies I get.
 
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That is only an accuracy observed due to a small sample size. When we say the probability of an event is x%, it means that the event should occur around x times out of a hundred trials. Taking a small number trials cannot give us and accurate prediction. For example if you roll a die only once, you would definitely observe some number. However that doesn't mean that the probability of getting that number is 100%.
You would observe that as you gradually increase the number of photons in your case, the number reflected back would be come closer and closer to 95%.
 
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