Answer:
Explanation:
The peak wavelength of the spectral distribution can be found by using Wien's displacement law:
where
is Wien's displacement constant
T is the absolute temperature
For the cosmic background radiation, the temperature is
T = 2.7 K
So, the corresponding peak wavelength is
Answer:
Explanation:
The work function of the metal corresponds to the minimum energy needed to extract a photoelectron from the metal. In this case, it is:
So, the energy of the incoming photon hitting on the metal must be at least equal to this value.
The energy of a photon is given by
where
h is the Planck's constant
c is the speed of light
is the wavelength of the photon
Using and solving for
, we find the maximum wavelength of the radiation that will eject electrons from the metal:
And since
1 angstrom =
The wavelength in angstroms is