fa02opth_sol

fa02opth_sol - PHY6938 Proficiency Exam Fall 2002 Optics...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: PHY6938 Proficiency Exam Fall 2002 September 13, 2002 Optics and Thermodynamics 1. Objects at finite temperature T emit electromagnetic radiation with a continuous spectrum, called Blackbody radiation. The radiated power per unit area and unit wavelength is given by the function F ( λ ) = 2 πhc 2 λ 5 1 exp( hc/λk B T )- 1 , where λ is the wavelength, c = 3 . 00 × 10 8 m/s is the speed of light, h = 6 . 26 × 10- 34 Js is Planck’s constant, and k B = 1 . 381 × 10- 23 J/K is Boltzmann’s constant. (a) Make a sketch of F ( λ ) as a function of λ . F( λ29 λ (b) The power density F ( λ ) has a maximum at a particular wavelength, λ max . Derive the relation T λ max ≈ 2 . 90 × 10- 3 Km. This result is known as Wien’s Displacement law. Hint: It may be useful to note that the two roots of the transcen- dental equation 5- x = 5 e- x are 0 and approximately 4.965. To find the maximum of F ( λ ) we have to take the derivative of F ( λ ) with respect to λ . Let x = hc λkT .....
View Full Document

This note was uploaded on 03/11/2012 for the course PHY 3900 taught by Professor Staff during the Fall '1 term at FSU.

Page1 / 3

fa02opth_sol - PHY6938 Proficiency Exam Fall 2002 Optics...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online