A photosensitive surface has work function . If photon of energy 3 falls on this surface, the electron comes out with maximum velocity of 4 10^6 ~m / s . When photon energy is increased to 7 then maximum velocity of photoelectron will be

Step-by-step solution

The relationship between incident photon energy E , work function , and maximum photoelectron kinetic energy K_ max is governed by Einstein's photoelectric equation: E = + K_ max , where K_ max = 1 2 m v_ max ^2 . For the first case, E₁ = 3 and v₁ = 4 10^6 m/s yields: 3 = + 1 2 m v₁^2 2 = 1 2 m v₁^2 For the second case with E₂ = 7 : 7 = + 1 2 m v₂^2 6 = 1 2 m v₂^2 Dividing these results eliminates the material-dependent constants: 6 2 = 1 2 m v₂^2 1 2 m v₁^2 3 = v₂^2 v₁^2 v₂ = 3 v₁ Substituting v₁ = 4 10^6 m/s give