NEET-XII-Physics
17: Light Waves
- #11The inverse square law of intensity (i.e. the intensity
∞1r2) is valid for a
(a) point source
(b) line source
(c) plane source
(d) cylindrical sourcedigAnsr: aAns : (a) point source
Intensity of a point source obeys the inverse square law.
Intensity of light at distance r from the point source is given by
`` I=S/\left(4{\,\mathrm{\,\pi r\,}}^{2}\right)`` ,
where S is the source strength.
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