Angle of Elevation
Suppose the girl wants to see the boy at the top of the Eiffel tower.
Her eyes will see towards to the top.
The line from the girl’s eyes to the top of Eiffel Tower is Line of Sight
To measure angle,
we draw a horizontal from the girl’s eyes
Horizontal is a line which is parallel to the ground
Angle between line of sight and horizontal when object is above eye level is angle of elevation
Note: In Angle of elevation, person is looking above.
Angle of Depression
Now suppose there is a boy at the top of tower.
He is watching a girl at the bottom
His eyes will see towards to the bottom.
The line from the boy’s eyes to the girl is Line of Sight
To measure angle,
we draw a horizontal from the boy’s eyes
Horizontal is a line which is parallel to the ground
Angle between line of sight and horizontal when object is below eye level is angle of depression
Note: In Angle of depression, person is looking below.