46. N drops of mercury of equal radii and possessing equal charges combine to form a big spherical 47. drop. Then the capacitance of the bigger drop compared to each individual drop is: (1) N times (2) N2/3 times (3) N1/3 times (4) N5/3 times A sheet of aluminium foil of negligible thickness is placed between the plates of a capacitor of capacitance C as shown in the figure then capacitance of capacitor becomes : Foil d/2 d/2 (1) 2C (2) C (3) C/2 (4) zero 48. Two mirrors are inclined at an angle e as shown in the figure. Light ray is incident parallel to one of the mirrors. Light will start retracing its path after third reflection if: (1) 0=45 (2) 0=30 (3) 0=60 (4) all three