Question

How do you determine the angle of sunlight?

Answer 1

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

Explanation:

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

minimum.

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