A photoelectric surface is illuminated successively by monochromatic light of wavelength λ and λ/2. If the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the first case, the work function at the surface of material is
A. hc/λ
B. 2hc/ λ
C. hc/3λ
D. hc/2λ
Answer:D
A photoelectric surface is illuminated successively by monochromatic light of wavelength λ and λ/2. If the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the first case, the work function at the surface of material is
A. hc/λ B. 2hc/ λ C. hc/3λ D. hc/2λ