A student performs an experiment on the photoelectric effect, using two materials A and B. A plot of Vstop versus v is given in the figure.
Explanation:-
(i) We know that where v0=Threshold frequency
(ii) By the differentiation of potential
hv=eV
Differentiating both sides we get h.dv=edV
Now, Using this formula
For metal A, h=6*10-34Js….(i)
For metal B, h=0.8*10-33…(ii)
Since the value of Plank's constant is not equal for both the experimental graphs, the experiment is inconsistent with Einstein's theory. However, the values are very close to 6.6*10-34Js due to experimental limitation and hence can be considered consistent with Einstein's theory.