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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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Question

Use Einstein’s photoelectric equation to show how from this graph, 
(i) Threshold frequency, and (ii) Planck’s constant can be determined.

Numerical
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Solution

eV0 =hυ - hυ

`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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2018-2019 (March) 55/3/3

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