Page 64 - Miracles of The Qur'an Vol. 3

Miracles of the Qur’an

An image of Warsaw in A radar image taken by satellite. This image,
Poland obtained using radar. formed using microwaves, shows a moun-
tainous region of Salt Lake City, Utah.

Radar is a location device used to determine the location, speed and
direction of mobile or stationary objects, and works by reflecting micro-
42
waves. The operating principle of radar bears a close similarity to the re-
flection of sound. For example, someone shouting in a valley or a cave
hears his own voice being reflected back to him. If we know how fast
sound travels through the air, we can calculate the distance and general
direction of the object it bounces off.
In the radar system, electromagnetic energy signals are used in very

much the same way. Signals with a microwave frequency are emitted to-
ward an object and then return after being reflected by it. This part of the
signal returning to the radar is called an "echo." Radar devices use this
echo to determine the direction and distance of the object doing the re-
flecting. 43 Since they also use electromagnetic energy, radio, television
and the human eye all bear a close resemblance to radar systems, though
their frequencies are ultimately different. In addition, radar uses the re-
flected energy known as the "echo," rather than directly transmitted en-
44
ergy as in these examples. Reflected signals are converted into numeri-

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