Is it true that the intensity of light is inversely proportional to the square of the distance from the source of light?

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True

False

answer is B.

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Detailed Solution

The above statement is False.
“The intensity of the light to an observer from a source is inversely proportional to the square of the distance from the observer to the source.” Light loses brightness or luminosity as it moves away from the source, according to inverse square law. For example, if you turn on a light in one corner of the room and then move away from the source, the light appears dim or less bright as the distance between you and the source increases (away from the source).
The inverse-square proportionality can be expressed thus:

I_{2} = I_{1} {(r_{1} r_{2})}^{2}

where

I_{1}

is the intensity at the original distance,

r_{1}

is the original distance),

I_{2}

is the intensity at the new distance and

r_{2}

is the new distance.
The correct statement would be that the intensity of light is inversely proportional to the square of the distance from the observer to the source of light.

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