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Light Intensity Formula:
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Light intensity, also known as irradiance, is the power of electromagnetic radiation per unit area. It measures how much light energy strikes a surface and is crucial in various fields including optics, photography, and solar energy applications.
The calculator uses the fundamental light intensity formula:
Where:
Explanation: This formula calculates the amount of light energy distributed over a given surface area, providing the intensity of illumination at that surface.
Details: Accurate light intensity measurement is essential for designing lighting systems, optimizing solar panel placement, ensuring proper illumination for photography and videography, and maintaining healthy plant growth in agriculture.
Tips: Enter the total radiant power in watts and the surface area in square meters. Both values must be positive numbers greater than zero for accurate calculation.
Q1: What is the difference between light intensity and brightness?
A: Light intensity is a physical measurement of power per unit area, while brightness is the subjective perception of light by the human eye, which depends on both intensity and wavelength.
Q2: What are typical light intensity values?
A: Full sunlight is approximately 1000 W/m², office lighting is about 300-500 lux (equivalent to specific W/m² depending on wavelength), and moonlight is around 0.001 W/m².
Q3: How does distance affect light intensity?
A: For point sources, light intensity decreases with the square of the distance (inverse square law), but this calculator assumes uniform illumination over the specified area.
Q4: Can this calculator be used for different light sources?
A: Yes, it works for any electromagnetic radiation source as long as you input the total radiant power and illuminated area.
Q5: What are the limitations of this calculation?
A: This assumes uniform distribution of light over the area and doesn't account for factors like angle of incidence, reflectance, or spectral distribution.