Stefan-Boltzmann’s law of radiation with Cobra4 Xpert-Link
Principle
According of Stefan-Boltzmann’s law, the energy emitted by a black body per unit area and unit time is proportional to the power “four” of the absolute temperature of the body. Stefan-Boltzmann’s law is also valid for a so-called “grey” body whose surface shows a wavelength independent absorption-coefficient of less than one. In the experiment, the”grey” body is represented by the filament of an incandescent lamp whose energy emission is investigated as a function of the temperature.
Benefits
- Simplified implementation: all pre-settings already prepared
- Intuitive, touch-optimized software
- Recording of all required measured values via one device
- Cost savings: No need for an additional measuring amplifier
Thermopile, Moll type
Shielding tube, for 08479-00
Meter scale, l = 1000 mm
Resistor 100 Ohm 2%, 1W, G1
Filament lamp 6V/5A, E14
Lamp holder E 14,on stem
Connecting cord, 32 A, 500 mm, red
Connecting cord, 32 A, 500 mm, blue
Connecting cord, 32 A, 1000 mm, red
Adapter, BNC-plug/socket 4 mm
Cobra4 Xpert-Link
PHYWE power supply, variable DC: 12 V, 5 A / AC: 15 V, 5 A
Barrel base expert
Tasks
- To measure the resistance of the filament of the incandescent lamp at room temperature and to ascertain the filament’s resistance R0 at zero degrees centrigrade.
- To measure the energy flux density of the lamp at different heating voltages. The corresponding heating currents read off for each heating voltage and the corresponding filament resistance calculated. Anticipating a temperature-dependency of the second order of the filament-resistance, the temperature can be calculated from the measured resistances.
What you can learn about
- Black body radiation
- Thermoelectric e. m. f.
- Temperature dependence of resistances