Question

Using the graph shown in the figure for stopping potential V/s the incident frequency of photons, calculate Planck's constant

Answer 1

Here,

ΔV₀ = 1.23 − 0 = 1.23 V

From Eienstein's Photoelectric equation

eV₀ = hv − ϕ₀

On differentiating it, we get

eΔV₀ = hΔv

h = \(\frac{e\Delta V_0}{\Delta v}\)

\(= \frac{(1.6 \times 10^{-19}) \times 1.23}{(8 - 5) \times 10^{-14}}\)

\(= 6.56 \times 10^{-34}\) Js

Answer 2

According to Einstein s photoelectric equation

In the given graph :