School of Physics Lecture Demonstration Manual

Na-13 Pasco Blackbody apparatus.

Published: Tuesday 05 June 2007 - Updated: Thursday 31 March 2011


To demonstrate the blackbody spectrum and the change in the spectrum as the temperature is raised.



Click on pictures to enlarge.

Blackbody Apparatus pic 1

Blackbody Apparatus Pic 2

Blackbody Spectrum Pic


The Pasco blackbody apparatus consists of a spectrometer, Light source, Infra red sensor, rotational motion sensor and science workshop data acquisition unit. To obtain a spectrum the voltage to the globe is initially adjusted to 10V and the spectrometer arm rotated so that the spectrum is clearly visible to the side of the entrance slit. The IR sensor is tared and the data acquisition is initiated. A slight pressure needs to be applied to the rotary motion sensor to ensure that no slipping occurs as the arm is rotated. Data acquisition is stopped and the spectrometer arm returned to its initial position. The Power supply for the globe is adjusted to 4 V and the above data acquisition procedure repeated. The following is a sample data run for three separate voltages applied to the blackbody globe.

Safety notes

Electrical Safety 


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