How Do You Calculate the Density of a Diffraction Grating?

AI Thread Summary
To calculate the density of a diffraction grating, the maximum order of diffraction (fifth-order) and the wavelength of light (475 nm) are used. The thickness (t) of the grating is calculated as 1.30625 x 10^-6 cm. To find the density in lines per centimeter, the relationship between thickness and line density must be established, typically using the formula density = 1/(2t). This conversion is necessary since the original calculation provided the thickness rather than the desired density. The final step involves applying this formula to derive the density of the grating in lines/cm.
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Homework Statement


A diffraction grating uses light with a wavelength of 475 nm to generate an interference pattern. if the highest order maximum that appears is the fifth-order. what is the density of the grating in lines/cm?


Homework Equations


sinθ = mλ / d
t= (m + 1/2) (λ) / 2


The Attempt at a Solution


t = (m + 1/2) (λ) / 2
t - (5 + 1/2) (475 x 10^-9) / 2
t= (2.6125 x 10^-6) / 2
t= 1.30625 x 10^-6 cm


so i got the answer in cm and t is for thickness, but the question wants the answer in lines/cm, and i don't know how to get it like that, so please anyone can help
 
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can anyone help??
 
maybe u can use 1/2t
 
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