Orange light of wavelength $6000\times {10}^{-10}\mathrm{m}$ illuminates a single slit of width $0.6\times {10}^{-4}\mathrm{m}$. The maximum possible number of diffraction minima (exclude at infinity) produce on both sides of the central maximum is ______

For obtaining secondary minima at a point path difference should be integral 

multiple of wavelength $\therefore \mathrm{dsin}\theta =\mathrm{n}\lambda \therefore \sin \theta =\frac{\mathrm{n}\lambda }{\mathrm{d}}$

For n to be maximum $\sin \theta =1,\mathrm{n}=\frac{\mathrm{d}}{\lambda }=\frac{6\times {10}^{-5}}{6\times {10}^{-7}}=100$

Total number of minima on one side = 99
Total number of minima = 198.