The following question is worth 1.5 marks, or 1 59a of your grade for this Ida. We have just derived Bragg's law: iridium] = 11.). for diffraction gratings. However, you must also have seen at some point the rule for Bragg diffraction in crystals: Msnil} = 111 -there is a factor of 2 here! Explain what the difference is beMeen these tw cases I formulae - i.e. explain why there's a "2' in the crystal diffraction formula, but no '2' in the diffraction grating formula! You may find the following image of crystal diffraction helpful; IA'BIJ' iii iii 00 S5 @El