Inverse Square Law Calculator

✖Intensity of Transmitted Light varies as the square of the cosine of the angle between the two planes of transmission.ⓘ Intensity of Transmitted Light [I_t]			+10% -10%
✖The distance from the light source.ⓘ Distance [d]			+10% -10%

✖Luminance refers to the amount of light emitted, reflected, or transmitted by a surface or object per unit area. It measures the brightness or intensity of the light perceived by an observer.ⓘ Inverse Square Law [L_v]

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Formula

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Inverse Square Law

Formula

`"L"_{"v"} = "I"_{"t"}/"d"^2`

Example

`"0.265118cd*sr/m²"="21cd"/("8.9m")^2`

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Inverse Square Law Solution

STEP 0: Pre-Calculation Summary

Formula Used

Luminance = Intensity of Transmitted Light/Distance^2
L_v = I_t/d^2
This formula uses 3 Variables

Variables Used

Luminance - (Measured in Lux) - Luminance refers to the amount of light emitted, reflected, or transmitted by a surface or object per unit area. It measures the brightness or intensity of the light perceived by an observer.
Intensity of Transmitted Light - (Measured in Candela) - Intensity of Transmitted Light varies as the square of the cosine of the angle between the two planes of transmission.
Distance - (Measured in Meter) - The distance from the light source.

STEP 1: Convert Input(s) to Base Unit

Intensity of Transmitted Light: 21 Candela --> 21 Candela No Conversion Required
Distance: 8.9 Meter --> 8.9 Meter No Conversion Required

STEP 2: Evaluate Formula

Substituting Input Values in Formula

L_v = I_t/d^2 --> 21/8.9^2

Evaluating ... ...

L_v = 0.265118040651433

STEP 3: Convert Result to Output's Unit

0.265118040651433 Lux -->0.265118040651433 Candela Steradian per Sq Meter (Check conversion here)

FINAL ANSWER

0.265118040651433 ≈ 0.265118 Candela Steradian per Sq Meter <-- Luminance

(Calculation completed in 00.004 seconds)

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Created by Aman Dhussawat

GURU TEGH BAHADUR INSTITUTE OF TECHNOLOGY (GTBIT), NEW DELHI

Aman Dhussawat has created this Calculator and 50+ more calculators!

Verified by Parminder Singh

Chandigarh University (CU), Punjab

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< 7 Laws of Illumination Calculators

Beer-Lambert Law

Go Intensity of Transmitted Light = Intensity of Light Entering the Material*exp(-Absorption per Concentration Coefficient*Concentration of Absorption Material*Path Length)

Fresnel's Law of Reflection

Go Reflection Loss = (Refractive Index of Medium 2-Refractive Index of Medium 1)^2/(Refractive Index of Medium 2+Refractive Index of Medium 1)^2

Refracted Angle using Snell's Law

Go Refracted Angle = arcsinh((Refractive Index of Medium 1*sin(Incident Angle))/(Refractive Index of Medium 2))

Incident Angle using Snell's Law

Go Incident Angle = arcsinh((Refractive Index of Medium 2*sin(Refracted Angle))/(Refractive Index of Medium 1))

Illumination by Lambert Cosine Law

Go Illumination Intensity = (Luminous Intensity*cos(Illumination Angle))/(Length of Illumination^2)

Lambert's Cosine Law

Go Illuminance at Angle of Incidence = Illumination Intensity*cos(Incident Angle)

Inverse Square Law

Go Luminance = Intensity of Transmitted Light/Distance^2

< 16 Advanced Illumination Calculators

Beer-Lambert Law

Go Intensity of Transmitted Light = Intensity of Light Entering the Material*exp(-Absorption per Concentration Coefficient*Concentration of Absorption Material*Path Length)

Fresnel's Law of Reflection

Go Reflection Loss = (Refractive Index of Medium 2-Refractive Index of Medium 1)^2/(Refractive Index of Medium 2+Refractive Index of Medium 1)^2

Refracted Angle using Snell's Law

Go Refracted Angle = arcsinh((Refractive Index of Medium 1*sin(Incident Angle))/(Refractive Index of Medium 2))

Incident Angle using Snell's Law

Go Incident Angle = arcsinh((Refractive Index of Medium 2*sin(Refracted Angle))/(Refractive Index of Medium 1))

Intensity of Light Transmitted

Go Intensity of Transmitted Light = Intensity of Light Entering the Material*exp(-Absorption Coefficient*Path Length)

Illumination by Lambert Cosine Law

Go Illumination Intensity = (Luminous Intensity*cos(Illumination Angle))/(Length of Illumination^2)

Number of Floodlighting Units

Go Number of Floodlighting Units = (Area to be Lighted*Illumination Intensity)/(0.7*Lumen Flux)

Lambert's Cosine Law

Go Illuminance at Angle of Incidence = Illumination Intensity*cos(Incident Angle)

Spectral Transmission Factor

Go Spectral Transmission Factor = Transmitted Spectral Emission/Spectral Irradiation

Spectral Reflection Factor

Go Spectral Reflection Factor = Reflected Spectral Emission/Spectral Irradiation

Utilization Factor of Electrical Energy

Go Utilization Factor = Lumen Reaching Working Plane/Lumen Emitting from Source

Spectral Luminous Efficacy

Go Spectral Luminous Efficacy = Maximum Sensitivity*Photopic Efficiency Value

Inverse Square Law

Go Luminance = Intensity of Transmitted Light/Distance^2

Specific Consumption

Go Specific Consumption = (2*Input Power)/Candle Power

Luminance for Lambertian Surfaces

Go Luminance = Illumination Intensity/pi

Luminous Intensity

Go Luminous Intensity = Lumen/Solid Angle

Inverse Square Law Formula

Luminance = Intensity of Transmitted Light/Distance^2
L_v = I_t/d^2

What law is inverse square?

Newton's law states: The gravitational attraction force between two point masses is directly proportional to the product of their masses and inversely proportional to the square of their separation distance.

How to Calculate Inverse Square Law?

Inverse Square Law calculator uses Luminance = Intensity of Transmitted Light/Distance^2 to calculate the Luminance, The Inverse Square Law formula is defined as a law stating that the intensity of an effect such as illumination or gravitational force changes in inverse proportion to the square of the distance from the source. Luminance is denoted by L_v symbol.

How to calculate Inverse Square Law using this online calculator? To use this online calculator for Inverse Square Law, enter Intensity of Transmitted Light (I_t) & Distance (d) and hit the calculate button. Here is how the Inverse Square Law calculation can be explained with given input values -> 1.018844 = 21/8.9^2.

FAQ

What is Inverse Square Law?

The Inverse Square Law formula is defined as a law stating that the intensity of an effect such as illumination or gravitational force changes in inverse proportion to the square of the distance from the source and is represented as L_v = I_t/d^2 or Luminance = Intensity of Transmitted Light/Distance^2. Intensity of Transmitted Light varies as the square of the cosine of the angle between the two planes of transmission & The distance from the light source.

How to calculate Inverse Square Law?

The Inverse Square Law formula is defined as a law stating that the intensity of an effect such as illumination or gravitational force changes in inverse proportion to the square of the distance from the source is calculated using Luminance = Intensity of Transmitted Light/Distance^2. To calculate Inverse Square Law, you need Intensity of Transmitted Light (I_t) & Distance (d). With our tool, you need to enter the respective value for Intensity of Transmitted Light & Distance and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.

How many ways are there to calculate Luminance?

In this formula, Luminance uses Intensity of Transmitted Light & Distance. We can use 1 other way(s) to calculate the same, which is/are as follows -

Luminance = Illumination Intensity/pi

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