Think of a ball around the antenna. This ball will receive all the radiation emitted, spread across its full surface.
Now what is the formula for the surface area of a sphere? It's (4 * PI * r^2).
That is, the surface of the sphere is relative to square of he radius.
This is where the inverse square law comes from - when you increase the distance, the radiation gets spread out over an increasingly big surface, and that surface grows by the square of the distance, which then gives the decrease in radiation as an inverse to the surface area, e.g. the inverse square law.
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BB-3 ago
Great. My apartment is in range of like 8 or 10 WiFi networks. One more reason to get out of the city.
RoundWheel ago
Proximity is be a major factor. Signal falls off at the square of the distance.
BB-3 ago
Would it not be the cube of the distance?
qwop ago
Think of a ball around the antenna. This ball will receive all the radiation emitted, spread across its full surface.
Now what is the formula for the surface area of a sphere? It's (4 * PI * r^2).
That is, the surface of the sphere is relative to square of he radius.
This is where the inverse square law comes from - when you increase the distance, the radiation gets spread out over an increasingly big surface, and that surface grows by the square of the distance, which then gives the decrease in radiation as an inverse to the surface area, e.g. the inverse square law.
EngelbertHumperdinck ago
Brilliant explanation. The surface area model makes so much sense. Thanks!