Light Intensity Calculator

Calculate the intensity of light based on the power of the light source and the distance from it using the inverse square law.

Input Parameters

Calculation Results

Calculation Formula

Intensity (I) = Power (P) / (4 * π * Distance²)

Where:
I = Intensity (W/m²)
P = Power of the light source (W)
π = Pi (approximately 3.14159)
Distance = Distance from the light source (m)

Light Intensity Calculator Usage Guide

Learn how to use the Light Intensity Calculator and its working principles

How to Use the Calculator

  1. Enter the power of the light source in watts (W) in the "Light Power (Watts)" field.
  2. Enter the distance from the light source in meters (m) in the "Distance (meters)" field.
  3. Click the "Calculate" button to compute the light intensity.
  4. The result will be displayed in the "Intensity (W/m²)" field.

Understanding Light Intensity

Light intensity is a measure of the power of light per unit area. It decreases with the square of the distance from the light source, following the inverse square law. This calculator helps you determine the intensity of light at a given distance from a light source of known power.

Example

If you have a light bulb with a power of 100 watts and you want to know the intensity of light 2 meters away, you would enter 100 in the power field and 2 in the distance field. The calculator would then show that the intensity is approximately 3.98 W/m².