10. If the intensity of light in double slit experiment from slit 1 and slit 2 are Io and 251o respectively, find the ratio of intensities of light at minima and maxima in the interference pattern. (a) 0 (b) 24 (c) 26 (d) +4414 11. 12. A proton of mass m and charge q enters a region of uniform magnetic field of a magnitude B with a velocity v directed perpendicular to the magnetic field. It moves in a circular path and leaves the magnetic field after completing a quarter of a circle. The time spent by the proton inside the magnetic field is proportional to: 1/2 (a) v (b) 1/2 (c) vo (d) v A ray of light is reflected by two perpendicular plane mirrors as shown. The angle 0 is equal to: 25 M (a) 65 (b) 25 (c) 50 (d) 90