Practice question

Given: Light of wavelength 350 nm is incident on a metal with work function 2.0 eV . What is the stopping potential? (Take h c = 1240 eV nm ) These values define the system as per NCERT data. Formula: E = h c/lambda = 1240/350 approx 3.54 eV. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: K_{max = E - phi_0 = 3.54 - 2.0 = 1.54 eV . V_0 = fracK_{maxe = 1.54 V . Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kg⁻¹ K⁻¹, m/s², 10⁻⁵ are properly used as per NCERT.