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Trollfaz
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Why is it that when I conduct the double slit experiment at home by shining light through 2 slits, I get no interference pattern but certain experiments are able to produce it?
The interaction between light and air is very weak, so visible light in air behaves pretty much as if it were in a vacuum. Free electrons on the other hand interact with just about everything', including random air molecules.Trollfaz said:Why is it that the air molecules don't cause the light to switch to a particle behaviour, like the.electrons?
Trollfaz said:Why is it that when I conduct the double slit experiment at home by shining light through 2 slits, I get no interference pattern but certain experiments are able to produce it?
If you take a thin piece of glass (microscope slide is ideal but the glass from a photo frame could do) deposit a layer of carbon ("lamp black") on it from a candle flame. Then scratch two very parallel lines on it, as close together as you can get with a fine needle (some practice is needed for this). Then shine the light from a cheapo laser pointer through it. It will give you a very convincing set of interfering fringes.Trollfaz said:Why is it that when I conduct the double slit experiment at home by shining light through 2 slits, I get no interference pattern but certain experiments are able to produce it?
Or you could just buy a diffraction grating or use a CD to achieve the same type of effect.sophiecentaur said:Then scratch two very parallel lines on it, as close together as you can get with a fine needle (some practice is needed for this).
Trollfaz said:Why is it that when I conduct the double slit experiment at home by shining light through 2 slits, I get no interference pattern but certain experiments are able to produce it?
The interference pattern of light refers to the alternating bright and dark fringes that appear when two or more light waves overlap and interfere with each other. This phenomenon is a result of the superposition of waves, where the amplitudes of the waves add or cancel out at different points in space.
Interference in light waves is caused by the interaction of two or more coherent light waves. Coherent light waves have the same wavelength, frequency, and phase, which allows them to interfere constructively or destructively with each other.
Constructive interference occurs when two waves with the same phase overlap and their amplitudes add together, resulting in a larger amplitude. This produces a bright fringe in the interference pattern. Destructive interference, on the other hand, occurs when two waves with opposite phases overlap and their amplitudes cancel out, resulting in a dark fringe in the interference pattern.
The interference pattern is affected by the distance between light sources through the principle of path difference. The path difference is the difference in the distance the two waves travel from their sources to a point in space. When the path difference is equal to a multiple of the wavelength, constructive interference occurs, and when it is equal to half a wavelength, destructive interference occurs.
Interference of light waves has many practical applications, such as in optical coatings, holograms, and diffraction gratings. It is also used in interferometers, which are instruments that measure small changes in distance or wavelength. Interference of light waves is also important in understanding the behavior of light in various optical devices such as lenses and mirrors.