Question

Light of two different frequencies whose photons have energies 1 eV and 2.5 eV respectively, successively illuminate a metallic surface whose work function is 0.5 eV. Ratio of maximum speeds of emitted electrons will be

(a) 1:4

(b) 1:1

(c) 1:5

(d) 1:2

Answer 1

The correct option is (d) 1:2.

Explanation:

According to Einstein's photoelectric equation, the maximum kinetic energy of emitted photoelectrons is