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

Step-by-step solution

According to Einstein's photoelectric equation, the maximum kinetic energy of emitted photoelectrons is K_ =h v- ₀ where h v is the energy of incident photon and ₀ is the work function. But K_ = 1 2 m v_ ^2 1 2 m v_ ^2=h v- ₀ As per question, Dividing eqn. (i) by eqn. (ii), we get aligned & v_ ₁ ^2 v_ ₂ ^2 = 0.5 eV 2 eV = 1 4 & v_ ₁ v_ ₂ = 1 4 = 1 2 aligned