- Sections
- A. General Materials & Mathematics
- B. Statics
- C. Kinematics & Dynamics
- D. Rotational Mechanics
- E. Gravitation & Astronomy
- F. Fluid Mechanics
- G. Vibrations & Mechanical Waves
- H. Sound
- I. Thermodynamics
- J. Electrostatics & Magnetostatics
- K. Electromagnetic Principles
- L. Geometrical Optics
- M. Wave Optics
- N. Spectra & Color
- O. Vision
- P. Modern Physics
I2-04. Wien's Law Of Thermal Radiation
Purpose
To show that hotter blackbodies radiate with shorter wavelength radiation.
Equipment
Variac, light bulb and filter assembly with two clear 150 Watt light bulbs, red, and
blue filters.
Images
Description
A variac is connected to two identical light bulbs in parallel, which are viewed behind
red and blue filters respectively. As the voltage is increased by the variac, the
lights glow more brightly, and more light is seen through the blue filter relative
to that of the red filter. Very little or no blue is seen at low voltages, whereas
red is seen to be emitted even at very low voltages.
References
H. Richard Crane, The cold night sky, TPT 22, 284 (1984). W. G. Rees and C. Viney,
On cooling tea and coffee, AJP 56, 434-437 (1988).
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See pagesi1. thermal properties of matter
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See pagesi2. transfer of heat
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See pagesi3. gases
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See pagesi4. changes of state
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See pagesi5. laws of thermodynamics
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See pagesi1. thermal properties of matter
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See pagesi2. transfer of heat
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See pagesi3. gases
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See pagesi4. changes of state
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See pagesi5. laws of thermodynamics
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