Calculate Perpendicular Shade

A simple calculator for the height or depth of a shadow of a horizontal screen on a perdenpicular wall. An example is the shadow from eaves on a house wall. The height of the Sun is given in degrees. Object length and shadow depth of height have the same unit, e.g. feet or meters. See also shadow casting for the shade length on a vertical ground.

Formulas:
s = l * tan(α)
α = arctan(s/l)

Sun altitude α:		°
Screen length l:		cm, m, ...
Shadow depth s:		cm, m, ...
Ratio depth-length:		%