47. In a Cinema hall, the distance between the projector and the screen is increased by 2%. Then the intensity of illumination on the screen is A.Decreased by 2% B.Decreased by 4% C.Increased by 2% D.Increased by 4%
Option B Solution: In a Cinema hall, the distance between the projector and the screen is increased by 2%. Then the intensity of illumination on the screen is decreased by 4%.
