question_answer 30)

It is a well known fact that during a solar eclipse the disc of the moon almost completely covers the disc of the sun. From this fact and from the information that sun's angular distance a is measured to be 1920", determine the approximate diameter of the moon. Given earth-moon distance .  

Answer:

During total solar eclipse, the disc of the moon completely covers the disc of the sun, so the angular diameters of both the sun and the moon must be equal.  Angular diameter of the moon,  Angular diameter of the sun     Earth-moon distance, Diameter of the moon,   .