Objective: Verify the inverse square law for the intensity of radiation from a source of light
According to the inverse square law, the intensity of radiation from a light source, i.e. the power per unit area, is inversely proportional to the square of the distance from the source. This will be investigated in an experiment using an incandescent light bulb. When the distance from the lamp is much greater than the size of the filament, such a bulb can be regarded as a point source of light. In order to measure the relative intensity of the radiation, a Moll thermopile is used.
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for the experimental setup of tubes of series S, 1014525 [U185002], Electron Tubes S](/thumblibrary/U185002/U185002_01_140_140_Tube-Holder-S-for-the-experimental-setup-of-tubes-of-series-S.jpg)
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(230 V, 50/60 Hz), 1003312 [U33020-230], Power Supplies](/thumblibrary/U33020-230/U33020-230_01_140_140_DC-Power-Supply-20-V-5-A-230-V-5060-Hz.jpg)
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![Graduated Ruler, 1 m, 1000742 [U8401550], Measurement of Length](/thumblibrary/U8401550/U8401550_01_140_140_Graduated-Ruler-1-m.jpg)
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