Optics: I do not understand what this question is asking

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The discussion centers on understanding a problem related to single slit diffraction and the calculation of irradiance ratios. The key question involves determining the ratio of irradiance I/I_0 at a point on the screen that is 3/4 of a wavelength farther from one edge of the slit compared to the other. Participants clarify that this distance can be interpreted in terms of wave interference from two coherent sources at the slit edges. The relationship between amplitude and intensity is emphasized, noting that intensity is proportional to the square of the amplitude. Overall, the conversation aims to clarify the application of the given information to solve the problem effectively.
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Homework Statement


Call the irradiance at the center of the central Fraunhofer diffraction maximum of a single slit I_0 and the irradiance at some other point in the patterm I. Obtain the ratio I/I_0 for some point on the screen that is 3/4 of a wavelength farther from one edge of the slit than the other.


Homework Equations


Irradiance for single slit diffraction
I=I_0sinc^2(β)
β=\frac{1}{2}kbsin\theta
k=\frac{2\pi}{\lambda}
b=slit size

The Attempt at a Solution


Well I know that when beta is equal to zero, the irradiance is at its maximum. But I do not know if this helps me or not. I honestly do not understand the question. 3/4 of a wavelength farther from one edge of the slit than the other? Don't I need the slit length? How can I make use of this information? Why does it say "than the other." What other point?

I really want to understand this problem. If anyone can help me I would much appreciate it!
 
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Xyius said:

The Attempt at a Solution


Well I know that when beta is equal to zero, the irradiance is at its maximum. But I do not know if this helps me or not. I honestly do not understand the question. 3/4 of a wavelength farther from one edge of the slit than the other? Don't I need the slit length? How can I make use of this information? Why does it say "than the other." What other point?

I really want to understand this problem. If anyone can help me I would much appreciate it!
Think of two coherent light sources, one at each edge of the slit. At a point that is 3/4 of a wavelength farther from one of those two sources than the other, how would the amplitude of the combined wave compare to the amplitude at a point where there was full constructive interference (maximum amplitude). How would the intensities be related? (ie how is intensity related to amplitude?).

AM
 
In other words you don't need a variable if you have a way to cancel it using the given information and perhaps setting up two equations or a ratio
 
Ohh! Okay that makes sense now! Thanks guys, I will give it a shot tomorrow. (Just finished studying :p)
 

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