How do you determine the angle of sunlight?

1 Answer
Jul 19, 2016

At noon, this angle is given by
#arc tan# (length of your horizontal shadow)/(your vertical height)


Defining angle of sunlight as angle of incidence of light rays

from Sun, this angle is the angle 'a' that the sunlight-direction makes

with the vertical. When sunlight strikes right from overhead, a = 0.

At sunrise and sunset on any day, sunlight strikes horizontally. So,

this angle is #90^o#.

At noon ( the instant midway between sunrise and sunset), this angle

is minimum, and correspondingly, the length of your shadow is


If you measure the length of the shadow at noon as L against your

height H,

#tan a = L/H#, and so,#

#a = arc tan (L/H)#

Of course, this varies between #latitude+- 23.4^o#, in a year