For this question, could someone please explain how the frequency of the wave is related to the voltage. ( I thought that we normally graph frequency against KE), also pls explain how I could use the graph to find the Plank's constant, work function, threshold frequency and why it works like that. Thanks in advance
Mod 7 photoelectric effect (1 Viewer)
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Vaibhav123456
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The stopping voltage required to stop the electrons is provided by: KEmax=eV where V is the stopping voltage. Therefore for each frequency the voltage would be equal to the kinetic energy of the photoelectrons. For example at 6 x 10^14 Hz the KEmax would be 0.16eV.
Using KEmax = hf - work function, when KE = 0 (when V = 0) the frequency on the graph (x-intercept) would indicate the threshold frequency (the graph should be V vs f). Planck's constant in terms of eVs would be the gradient as h = E/f. The work function would be the absolute value of the y-intercept (when f = 0) because when f = 0, KEmax = 0 - work function.
Using KEmax = hf - work function, when KE = 0 (when V = 0) the frequency on the graph (x-intercept) would indicate the threshold frequency (the graph should be V vs f). Planck's constant in terms of eVs would be the gradient as h = E/f. The work function would be the absolute value of the y-intercept (when f = 0) because when f = 0, KEmax = 0 - work function.