Question

How do you determine the angle of sunlight?

Answer 1

Hint:In order to determine angle of sunlight first understand how it varies with time. Then by using an example show how to determine the angle when height of an object and its shadow is given.

Complete answer:
Angle of sunlight can be considered as the angle of incidence when the light strikes on a surface.During the time of sunrise and sunset light travels horizontally and hits the object at$0^\circ $.At noon, we can see the sunlight falls right above our head so the sun rays strike the object at $90^\circ $.

Consider a time other than sunrise/sunset or noon. In order to find the angle of sunlight first consider a block of height A .When light is incident on the top of the object. It’s shadow will fall on the ground .Let the length of shadow be B. Now we will get a right angled triangle with height A and base B. Assume angle of sunlight be $\theta $.

Now we know that
$\tan \theta = \dfrac{A}{B}$
$\therefore\theta = {\tan ^{ - 1}}\left( {\dfrac{A}{B}} \right)$
Hence we can find the angle of sunlight.

Note:To determine the angle of sunlight first draw a figure considering sunlight is falling on an object then by knowing the height of the object and length of shadow we can calculate the angle.
$\tan \theta = \dfrac{{opposite}}{{adjacent}}$
Shadow of the object can change with respect to time .Length of the shadow will not be the same as object height so never assume both distance of shadow and height of the object as equal.