Correct option : (1) 5.5×1011
Explanation :
The threshold wavelength will be given by
Hence light of wavelength 6216 Å will not emit photoelectrons from the metal surface. Since the total intensity of light is equally distributed among the wavelengths, the intensity which each wavelength will have is
Power incident on the surface due to each wavelength is
1.2×10–3 × 10–4 J/s (A = 10–4)
Power incident on 1 cm2 = P1 = 1.2×10–3×10–4 = 1.2×10–7 J/s
∴ The number of electrons emitted by λ1 = number of photon incident