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Question
State how will you use this graph to detennine the value of Planck's constant.
Solution
From the graph the slope , tan θ = `(V_s)/f`
⇒ tan `theta =h/e [∵V_s =h/ef]`
∴ h = Planck's constant = e tan θ
Thus, knowing the slope we can get the value of 'h' - Planck's constant
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