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Question
Use Einstein’s photoelectric equation to show how from this graph,
(i) Threshold frequency, and (ii) Planck’s constant can be determined.
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Solution
eV0 =hυ - hυ0
`V_0 = h/e(υ - v_0)`
Point A on the graph shows threshold frequency.
eV0 = hv - Φ0
`V_0 = h/e υ - (phi _0)/e`
Slope of the given graphs gives `h/e`
Slope `= h/e`
h = e × slope of the graph
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