Ans. 1.57 V.
cathode surface when 3000 Å light strikes it.
. A retarding potential of 0.5 V is required to block
the movement of electrons from the cathode of a
photoelectric cell when violet light of wavelength
4000 Å strikes its surface. Find (i) the work function
of this surface, (ii) the threshold frequency, (iii) the
energy of light of wavelength 3000 Å and (iv) the
maximum energy of the electron emitted from the
Answers
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