VISUAL  PHYSICS  ONLINE

7.1   THE NATURE OF LIGHT

        QUANTUM MODEL

 

P71 010

 

(A1)   Estimate the temperature of the surface of the Sun, given that the Sun emits light at a peak wavelength around 550 nm.

 

(A2)   Which star is hotter, a blue or a red star. Explain.

 

 

 

 

 

 

 

 

 

 

 

 

    

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

View solution below only after you have completed the answering the question.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Solution

(A1)

 Wien’s Displacement Law 

            lpeak T = 2.9´10-3  m.K

          lpeak = 550 nm = 550 ´10-9  m     T = ? K

         

(A2)

          lblue < lred   à   Tblue > Tred