A photon of wavelength 250 nm strikes a metal surface. The ejected electron has a de Broglie wavelength of 1.0 × 10⁻⁹ m.
E = hc/λ ≈ 7.951×10⁻¹⁹ J. KE = h²/(2mλ²) ≈ 2.412×10⁻¹⁹ J. W₀ = E - KE ≈ 5.539×10⁻¹⁹ J.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Quantum Mechanical Model - de Broglie Heisenberg and Schrodinger