Two slits are separated by 0.180 mm. An interference pattern is formed on a screen 80.0 cm away by 656.3-nm light. Caclulate the fraction of the maximum intensity 0.600 cm above the central maximum.(adsbygoogle = window.adsbygoogle || []).push({});

So to my understanding

we know the wave-length = 656.3nm

We know the distance between the two slits = .180 mm

and we know how far away we are from the screen .800 m

I know Light intensity(maximum)=

I=I_max*(cos^2(pi*d*sin(thetha)/lambda))

I know the relatship between phi and lambda as well..

but I don't know how to go from here. Maybe I am heading the wrong directon with is? Any suggestions would be helpful.

Thank you.

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# Homework Help: Interference Question

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