A photon of energy 4eV is incident on a metal surface whose work function is 2eV. The minimum reverse potential to be applied for stopping the emission electrons is
a) 2V b) 4V c) 6V d) 8V
Correct Answer is a) 2V
12mv2max=hv???=4eV?2eV=2eV12mvmax2=hv???=4eV?2eV=2eV
Now, eV?=2eVeV?=2eV
?V?=2V?V?=2V
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