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Question
Light from Balmer series of hydrogen is able to eject photoelectrons from a metal. What can be the maximum work function of the metal?
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Solution
Let the maximum work function of the metal be W.
The energy liberated in the Balmer Series (E) is given by
`E = 13.6(1/n_1^2 - 1/n_2^2)`
For maximum work function, maximum energy of Balmer's series is taken.
Now, n1 = 2, n1 = ∞
`therefore E = 13.6(1/2^2)`
=` 13.6 xx 1/4 =3.4 eV`
Here,
W = E
Thus, maximum work function of metal is 3.4 eV.
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