a. Explain why the graphs ofFigure 38.3 are mostly horizontal for ΔV > 0.

b. Explain why photo-electrons are ejected from the cathode with a range of kinetic energies, rather than all electrons having the same kinetic energy.
c. Explain the reasoning by which we claim that the stopping potential V_stop indicates the maximum kinetic energy of the electrons.

Transcribed Image Text:

A more intense light causes a larger current. Intense light No current flows if AV<-Vstop- Weaker light Δν -Vstop The current becomes inde- pendent of AV for AV>0.