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Question
Use Einstein's photoelectric equation to explain the observations from this graph ?
Solution
The Einstein's photoelectric equation is \[K_{max} = \frac{1}{2}m \nu^2_{max} = h\nu - \phi_o\]
From the graph, we noticed that
(i) The value of stopping potential is different for radiation of different frequencies.
\[\text { As } \]
\[e V_o = h\nu - \phi_o \]
\[\text { Hence }, V_o \propto \nu\]
(ii) The value of stopping potential is more negative for radiation of higher incident frequency.
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