#AstronomyImageOfTheDay
Launch and Landing
A composite of three consecutive exposures, this night skyscape follows the January 7 launch and first stage landing of a Falcon 9 rocket from a beach on planet Earth's space coast.
@MinutePhysics
Launch and Landing
A composite of three consecutive exposures, this night skyscape follows the January 7 launch and first stage landing of a Falcon 9 rocket from a beach on planet Earth's space coast.
@MinutePhysics
#PhysicsEquation
Wien's law states that for a blackbody such as a star, out of all the radiation, there will be a particular peak wavelength corresponding to that black body. A black body is a perfect absorber and emitter of radiation. A star or a light bulb are good approximations of a black body.
Wien's law can be understood with a simple example. A campfire is a good source of heat than that of light. Why?
The temperature of a campfire is about 1500 K. Using this equation, this gives peak wavelength of 2000 nm.% of its radiation is at wavelengths longer than 1000 nm, and only a tiny proportion at visible wavelengths (390-700 nm). Consequently, a campfire can keep one warm but is a poor source of visible light.
However Wien did not go further. He only explained the peak of the curve. What happens at larger and shorter wavelength was still not known. Max Planck was the one who completely explained the theory of black body radiation and he calls it the "most strenuous" work of his life. Planck said that the energy is emitted in discrete amounts rather than in continuous form and this formed the basics of quantum physics.
Wien's law states that for a blackbody such as a star, out of all the radiation, there will be a particular peak wavelength corresponding to that black body. A black body is a perfect absorber and emitter of radiation. A star or a light bulb are good approximations of a black body.
Wien's law can be understood with a simple example. A campfire is a good source of heat than that of light. Why?
The temperature of a campfire is about 1500 K. Using this equation, this gives peak wavelength of 2000 nm.% of its radiation is at wavelengths longer than 1000 nm, and only a tiny proportion at visible wavelengths (390-700 nm). Consequently, a campfire can keep one warm but is a poor source of visible light.
However Wien did not go further. He only explained the peak of the curve. What happens at larger and shorter wavelength was still not known. Max Planck was the one who completely explained the theory of black body radiation and he calls it the "most strenuous" work of his life. Planck said that the energy is emitted in discrete amounts rather than in continuous form and this formed the basics of quantum physics.
