関連ワード:  what is diffraction class 12    what is diffraction class 12 physics    what is diffraction class 12th physics    what is diffraction class 12 wave optics    what is diffraction class 12 ncert    what is fresnel diffraction class 12    what is fraunhofer diffraction class 12    what is diffraction grating class 12    what is diffraction class 12 cbse    what is diffraction of light class 12