How is a single photon fired in the double slit experiment?

[AJ_2010]

The basis of the well known experiment is to fire one photon at a double slit 'wall' and measure the wave pattern produced on a screen behind it.

Now as is evident, one particle is seen to act like a wave, which is a fundamental contradiction.


I have couple of fundamental questions regarding the experimental procedure.

(1) How can it be assured that only one photon is being 'fired' at the slits?

(2) If indeed one photon is being fired, then surely this photon has a given velocity aimed at one slit or the other. So if I were to draw a line from the emitter to the slit it is pointing at then this should be the slit that this single photon passes through. Is this how the experiment is set up?
The only way I can work it out in my head is if the supposed one photon emission is in fact numerous, and these are emitted at various angles that encompass the two slits.




Or am I blatantly just repeating the paradox by asking these questions?

 

[ZapperZ]

You might want to start by first read one of the entry in the FAQ thread in the General Physics forum.

Secondly, you might want to do a search on the principle of "superposition". I think you are approaching this from a purely a classical understanding, evidenced by your notion that you actually know where your photon is being aimed at. This already forced your situation into a particular scenario.

And yes, this question has been asked numerous times on here.

Zz.

 

[AJ_2010]

Thanks.
Read the FAQ and realize that my questions are basically non-questions.

I watched a BBC program last night about 'REALITY'.
They went on to explain about the particle/wave nature of light and the classical physics experiment about the dual slits.
The way they were explaining it was confusing. (To me at least).
In that their proof of the wave-like nature was solely down to one 'particle'/'photon' of light being able to go through both slits at the same time. But not explaining how a single photon was emitted nor explaining which slit the emitter was pointing at.