Question

39 * The spectral measurement of the light emission of a star indicates a maximum light intensity for a wavelength around 700 nm. At what temperature could the surface of this star be?

A. None of these other responses

B. 300 K

C. 10,000 K

D. 0 K

E. 4000 K

F. 1000 K

Answer 1

the surface temperature of a star and the wavelength of emitted by a star can be related using Wien’s displacement law,

λm T = b where, b = 2.89 x 10-3 mK—it is the Wien’s constant

                        T—surface temperature of the star

                        λm –wavelength corresponding to maximum intensity of radiation

given : λm = 700 nm = 700 x 10-9 m

λm T = b

T = b/ λm = 2.89 x 10-3 /700 x 10-9 = 4.128 x 103 K = 4128 K

The surface temperature of the star is T = 4128 K

Answer: A. None of these other responses