Suppose you illuminate two thin slits by monochromatic coherent light in air and find that they produce their first interference
minima at ± 35.09 ∘ on either side of the central bright spot. You then immerse these slits in a transparent liquid and illuminate them with the same light. Now you find that the first minima occur at ± 19.38 ∘ instead. What is the index of refraction of this liquid?
Because even though the moon is smaller, therefore a weaker gravitational pull, the moon is much closer to the earth than the sun, thus having a greater gravitational pull