Related Resources: excel calculators

Planks Law Spreadsheet


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Engineering Excel Calculators Spreadsheets

This workbook computes and displays the spectral blackbody emissive power for a number of source temperatures. This new version also allows the user to display the spectral blackbody emissive power for a particular temperature and evaluates the integral over a wavelength range selected by the user (replicating the tabulated blackbody radiation functions). (See the cyan-colored lines in the figure below.) Another sheet is this workbook includes tabulated data for the spectral transmissivity of two types of glass, one of them a standard glass, the other a "low-E" (low-emissivity) glass. The function for blackbody emissive power, this tabulated data and Simpson's Rule may be used to find the total transmissivity of the two glasses.

Download: Plank's Law Calculator

Planck's law describes the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium at a given temperature T, when there is no net flow of matter or energy between the body and its environment.

Spectral Blackbody Emissive power

Credit: Professor Robert J. Ribando