How do diffraction patterns change with laser and filtered light?

AI Thread Summary
When a HeNe laser illuminates an opaque plate with a specified aperture, it produces a distinct diffraction pattern on a screen 4 meters away. Replacing the aperture with two long rectangular slits results in a more complex interference pattern, requiring a sketch of intensity versus position. Substituting the laser with a normal electric filament bulb and a red filter broadens the diffraction pattern due to the longer wavelength of red light, leading to a different visual outcome on the screen. The relationship between the distance to the screen, slit separation, and wavelength is crucial for understanding the observed patterns. Ultimately, the change in light source significantly alters the diffraction characteristics.
planesinspace
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1. The problem
A HeNe laser (wavelength = 633nm) is used to illuminate an opaque plate containing a a specified aperture. The light which passes through the aperture falls on a screen at a distance of 4 m from the aperture plate.

c) The aperture is replaced by two long rectangular slits, each of width 0.050mm and with their centers separated by 0.150mm. Make a third sketch of intensity vs position again with a numerical scale.

d)With the same aperture from c, the laser light source is replaced by a normal electric filament light bulb plus a red filter. Explain what will now be seen on the screen and why it differs from the results with a laser,


Homework Equations


c)I have drawn a wave like with a single slit diffraction, in an envelope with another wave. I used this equation y= m*lamda*D/d
where D = distance to screen and d = distance from centers of slits.

d) y= m*lamda*D/d

The Attempt at a Solution



c)So for y i got 0.01688, so I'm not sure whether to use this as my numerical scale, and whether to draw two separate waves or the wave envelope phenomena i'v seen in my textbook.

d)Due to y= m*lamda*D/d, y is proportional to lamda, so red being the highest wavelength , y will increase and the diffraction pattern will broaden.
 
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planesinspace said:
I have drawn a wave like with a single slit diffraction, in an envelope with another wave. I used this equation y= m*lamda*D/d
where D = distance to screen and d = distance from centers of slits.

I think it's more interested in what you'd see on the screen, not how the wave diffracts..
 
The full question says "make a sketch graph oh the intensity vs position on the screen."
so I am just using those graphs where there are a series of curves / maxima and minima on the x axis.
 
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