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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?
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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