Question

assuming that moons diameter subtends an angles of 30' at the eye of an observer,find how far from the eye a coin of 1 inch must be kept so it fully coveres the moon

Answer 1

if u draw the figure a cone with its end points as the eye and moon and if take coin and the moon u get frustum

Answer 2

if you brother figure of cone which its endpoints as the eye and moon and if take coin and the moon you get frustum