If the Sun passes directly overhead on at least one day per year, then
A)you are within 23.4° latitude of the equator.
B)you are within 66.6° latitude of the equator.
C)you must be exactly on the equator.
D)you could be anywhere because this occurs at least once per year at any location on the Earth.

Question

Quizplus · Accepted Answer

The Sun passes directly overhead (i.e., the zenith) at noon on the two equinoxes each year only at locations on the equator (0° latitude). However, the Sun pass into the zenith at least once a year at places other than the equator, but it will not stay there for more than an instant. Therefore, the only way for the Sun to pass directly overhead on at least one day per year, means that the location is within 23.4° of the equator (i.e., the Tropics of Cancer and Capricorn). Beyond these latitudes, the Sun will never be directly overhead.

If the Sun Passes Directly Overhead on at Least One