KIT OF BLACK BODY RADIATION

KIT OF BLACK BODY RADIATION The kit for studying radiation includes a radiometer, Leslie’s cube and a Stefan-Boltzmann lamp. This kit will enable students to measure the radiation of a black body from sources with a wide range of temperatures. Leslie’s cube can be used as source of black body radiation up to 120°C, whereas the different faces of the same cube will enable to study emissivity. Stefan-Boltzmann lamp can be used to study black body radiation from 3000 to 3500 K. RADIOMETER Instrument used to measure the energy of a beam of radiations (in W/m2). The detector is a thermopile consisting of a set of thermocouples connected in series. This thermopile is installed inside a housing of aluminium to keep temperature stability. An additional shutter mounted on the housing cuts the input radiation when the zero line of amplifier is adjusted. This detector has a fl at spectral response of 0.3 μm in ultraviolet band, and of 15 μm in infrared band. The detection area is of approximately 2 mm2 and it is small enough to measure the energy in a laser beam. For wide radiation sources, the instrument is sensitive in a cone-shaped angle of 60°. TECHNICAL CHARACTERISTICS • Detector: a thermopile with 14 junctions • Spectral range: 0.3 to 15 μm • Sensitivity: 1000 W/m2 – 1 W/m2 on 4 ranges • Controls: change of range, zero adjustment, detector shutter • Dimensions: 12 (h) x 9.5 (w) x 22.5 cm (d) LESLIE’S CUBE It has been designed to study thermal radiation versus temperature and surface; it consists of a cube of brass with white and black sides and sides of matt and polished metal. The thermal emittance of sides varies from the dark part to the polished metal according to a factor of 20. A pipe for inserting a thermometer is available on the top of the cube. Filling the cube with warm tap water will enable to measure the radiation on the radiometer. TECHNICAL CHARACTERISTICS • Dimensions: cube of 7.5 cm • Material: brass • Sides: black side, white side matt brass, polished brass • Alcohol thermometer: 0° to 120°C STEFAN-BOLTZMANN LAMP It is used to measure radiation versus temperature. This tungsten lamp is a radiation source that enables to measure the energy radiated versus temperature. This ratio is the well-known Stefan-Boltzmann law of radiation. Starting from the current crossing the lamp and from the voltage across it, students will be able to calculate the resistance of fi lament. Then, starting from the variation of fi lament resistance, they can also determine temperature. The equipment also includes a low-voltage power supply unit 0 – 20 V, 0 – 5 A.