Author: HamadyHamady
Date: Sep 3, 2008 10:33
In the eleventh verse of Surat az-Zukhruf, rain is defined as water
sent down in "due measure". "It is He (God) Who sends down water in
due measure from the sky" (Qur’an, 43:11)
Indeed, rain falls on the earth in an unerring measure.
The first of the measures related to rain is its speed of descent.
When dropped from a height of 3937 feet, an object having the same
weight and size as a rain-drop would continuously accelerate and fall
on the ground at a speed of 347 miles/h. The average speed of
raindrops, however, is only 9.3-12.4 miles/h.
The reason for this is that the raindrop has a special form that
increases the frictional effect of the atmosphere and helps it fall on
the ground more slowly. A glance at the figures below is sufficient to
understand the disaster the earth would face every time it rained if
rain raindrops were in a different form, or the atmosphere did not
have the quality of friction.
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