(a) With the help of a suitable diagram explain why the Sun is visible to us two minutes before the actual…
(a) With the help of a suitable diagram explain why the Sun is visible to us two minutes before the actual sunrise and two minutes after the actual sunset.
(b) Name the phenomenon responsible for apparent flattening of the Sun’s disc at sunrise and sunset.
Solution
(a) The duration of the day becomes approximately 4 minutes longer due to atmospheric refraction. We can see the sun when it is below the horizon in the morning. The rays of light from the sun below the horizon(s) reach to our eyes due to refraction of light 2 minutes before it actually rises. Similarly the sun can be seen about 2 minutes after it actually set. Thus the duration of day time increases by 4 minutes (2 minutes each time at the time sunrise or sunset).
