If there is only one opening in a double-slit apparatus, interference patterns typically associated with the double-slit experiment would not occur. The interference pattern arises due to the constructive and destructive interference of waves passing through the two slits. With only one opening, there would be no second slit for the waves to interfere with.
Instead, you would observe a diffraction pattern. When a wave encounters an obstacle or aperture, it diffracts or spreads out. This diffraction pattern is characterized by a central maximum and a series of smaller maxima and minima on either side. The specific pattern depends on the size and shape of the aperture.
To observe or prove the absence of interference patterns when only one opening is present, you can conduct the following experiment:
Set up a double-slit apparatus with two slits and a screen behind it to observe the interference pattern. Make sure the slits are narrow and closely spaced.
Capture the interference pattern on the screen and record the results.
Next, block one of the two slits, leaving only one opening. This can be achieved by placing an opaque barrier or cover over one of the slits.
Repeat the experiment with the single opening and observe the pattern on the screen.
If interference is absent, you should observe a diffraction pattern with a central maximum and smaller maxima and minima on either side. The diffraction pattern will have a different distribution compared to the interference pattern obtained with both slits open. This change in pattern would support the conclusion that interference requires two slits and would not occur with just one opening.
It's worth noting that the results of the experiment would depend on various factors such as the wavelength of the waves used, the distance between the slits or opening, and the size of the opening. Experimental observations and theoretical calculations can provide further confirmation of the absence of interference and the presence of diffraction patterns in this scenario.