Inverse-Square Law Calculator
Compute illuminance E = I / d² from luminous intensity and distance.
Input Data
Input Luminous intensity I.
cd
Input Distance d.
m
Results
250lx
E = I / d².
At a glance:Inverse-Square Law Calculator: enter parameters to compute results; complements related calculators.
Formula
E = I / d².
How to Use
- Enter luminous intensity (cd) and distance (m).
- It returns illuminance (lx).
Case Studies
I=1000 cd, d=2 m → E=250 lx
E = 1000/4 = 250 lx.
FAQ
Why falls with d²?
Flux spreads over a sphere of area ∝ d², so E ∝ 1/d².
Related Tools
References
Content review: Calculatorism Science Team. Formula and numeric tests verified; results for reference only.