Question

Due to atmospheric refraction of sunlight, the time from sunrise to sunset is lengthened by about:
(a) 6 minutes
(b) 2 minutes
(c) 4 minutes
(d) 5 minutes

Answer 1

4 minutes

Because of the atmospheric refraction of sunlight, we can see the sun about two minutes before the actual sunrise and two minutes after the actual sunset. Therefore, the time from sunrise to sunset is lengthened by about four minutes (two minutes because of advanced sunrise and two minutes because of delayed sunset).