White light containing wavelengths from 405 nm to 760 nm falls on a grating with 7510 lines/ cm. How wide is the first-order spectrum on a screen 2.29 m away?(adsbygoogle = window.adsbygoogle || []).push({});

Is this correct

sin theta= (1)*(4.05e-7m)/(1.33e-6m)= 0.305 theta=17.8

location= 2x(tan 17.8)= (2*2.29)*0.321=1.47m

sin theta= (1)*(7.60e-7m)/(1.33e-6m)= 0.571 theta=34.8

location= 2x(tan 34.8)= (2*2.29)*0.695= 3.18m

so then should the answer to the question be

3.18m+1.47m/2= 2.33m

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# Homework Help: Diffraction grating

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