A certain battery can power a 100 ohm-resistance device for 4 hours. how long can the battery power a 200 ohm device?
1 answer:
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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