# inverse square law

#1
HI, can some help me with this question
https://postimg.cc/6ThKLt0b
0
3 years ago
#2
Inverse square law means relative light intensity is inversely proportional to square of distance

hence

If distance doubles, light intensity is multiplied by factor 1/4
If distance halves, light intensity is multiplied by 4

Spoiler:
Show

Method 1:
Calculate the constant k by using

Replace light intensities and calculate distance
Replace distance and calculate light intensity

Method 2:
Since
is a constant
hence

hence replace one pair of known values of intensity and distance
replace one light intensity and calculate unknown distance
replace one distance and caluclate unknown light intensity
Last edited by username3249896; 3 years ago
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