Question

If the maximum K.E. of electrons emitted by a photocell is 4cV, what is the stopping potential?

Answer 1

K.E. = eV0
where e= charge on the electron.
         V0= stopping potential
given kinetic energy of an electron is 4 eV.
To convert it into  joule we multiply  it by e. (As 1 eV = 1.6 X 10-19J

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