(b) Photocurrent reduces to zero, when maximum kinetic energy of
the emitted photoelectrons equals the potential energy e V0 by the
retarding potential V0 Einstein’s Photoelectric equation is
eV0 = hn – f 0  = hc
λ  – f 0
or,
l = hc/(eV0 + f0)
34
8
(6 63
10
Js)
(3
10 m/s)
(0 60eV
2