In a historical experiment to determine Planck's constant, a metal surface was irradiated with light of different wavelengths. The emitted photoelectron energies were measured by applying a stopping potential. The relevant data for the wavelength ( λ ) of incident light and the corresponding stopping potential V 0 are given below: λ μ m V 0 V o l t 0.3 2.0 0.4 1.0 0.5 0.4 Given that c = 3 × 10

Step-by-step solution

K E m a x = h C λ - ϕ e V 0 = h C λ - ϕ 1.6 × 10 - 19 × 2 = h × 3 × 10 8 3000 × 10 - 10 - ϕ .....(i) 1.6 × 10 - 19 × 1 = h × 3 × 10 8 4000 × 10 - 10 - ϕ .......(ii) From (ii) ϕ = h × 3 × 10 8 4000 × 10 - 10 - 1.6 × 10 - 19 Using value of ϕ in equation (i), we get 1.6 × 10 - 19 × 2 = h × 3 × 10 8 3000 × 10 - 10 - h × 3 × 10 8 4000 × 10 - 10 + 1.6 × 10 - 19 1.6 &#2