Q2. In the experiment of diffraction grating to find the wavelength of illumination source, the following information are given, the first order of the grating (15000lines/inch) is opted for measurement. The distances are taken in cm. (10) S/No L(grating-screen) Y1 (+ve first order Y2(-ve first separation from zero order) order from zero (wavelength) order) 1 31 5.8 2 26 4.8