In an experiment aimed to disprove Einstein's photoelectric equation,how did Millikan prove it?

(N/A) Einstein's photoelectric equation is given by:
$\frac{1}{2} m v_{\max }^{2} = h \nu - \phi_{0}$
Since the maximum kinetic energy is related to the stopping potential $V_{0}$ by the relation:
$\frac{1}{2} m v_{\max }^{2} = e V_{0}$
Substituting this into the photoelectric equation,we get:
$e V_{0} = h \nu - \phi_{0}$
Rearranging for $V_{0}$:
$V_{0} = \left( \frac{h}{e} \right) \nu - \frac{\phi_{0}}{e}$
This equation is of the form $y = mx + c$,representing a straight line where the slope is $\frac{h}{e}$.
Millikan performed a series of experiments measuring the stopping potential $V_{0}$ for different frequencies $\nu$ of incident radiation. He plotted a graph of $V_{0}$ versus $\nu$,which resulted in a straight line. The slope of this line was found to be $\frac{h}{e}$.
By using the known value of the elementary charge $e$,Millikan calculated the value of Planck's constant $h$ to be approximately $6.626 \times 10^{-34} \text{ Js}$,which matched the previously accepted value.
Thus,while Millikan initially intended to disprove Einstein's theory,his experimental results provided strong evidence for its validity,confirming the photoelectric equation with great precision across various alkali metals.