4. The graph below shows the wavelength of light for two stars as a function of their power density, one of the sun and the other being our next closest star, Proxima Centauri. Sun Proxima Centauri Wavelength (nm) (a) Does the sun or Proxima Centauri have a greater surface temperature? Explain your answer. Power Density (1013 watts/m')

4. The graph below shows the wavelength of light for two stars as a function of their power density, one of the sun and the other being our next closest star, Proxima Centauri. Sun Proxima Centauri Wavelength (nm) (a) Does the sun or Proxima Centauri have a greater surface temperature? Explain your answer. Power Density (1013 watts/m')

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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The wavelength of the peak of the blackbody distribution was found to follow Wein’s Displacement Law. Calculate the peak wavelength of a bluish-white star that radiates at temperature 20000 K. a) 145 nm b) 100 nm c) 114 nm d) 155 nm
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Q1 Find the total energy and the greatest wavelength of the energy emitted from the surface of the sun if you know that the amount of illumination emitted from the surface of the sun will increase by 10⁶ * 6 times when its surface temperature increases by 100 k (σ = 5.67× 10⁻⁸ w/m²K⁴ )
In one lake, a researcher discovered that any change of 10 meters in depth reduces the amount of light reaching that depth by 22.8%. a.What is the 10-meter percent change in the amount of light available under water in this lake? b.What is the 10-meter decay factor in the amount of light available under water in this lake?
2. a) At what wavelength is the peak in the thermal ("blackbody") spectrum of the Sun? What about for the Earth? Make sure you show how you got these numbers, and then b) Give a term for the part of the electromagnetic spectrum in which these peaks occur (e.g., x-ray, UV, Visible, IR, microwave, etc.). c) What is the total flux emitted in each case (in W m ²)?
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