Question

Light of frequency 6·4 × 10¹⁴ Hz is incident on a metal of work function 2·14 eV. The maximum kinetic energy of the emitted electrons is about :

Figure shows the variation of photoelectric current measured in a photo cell circuit as a function of the potential difference between the plates of the photo cell when light beams A, B, C and D of different wavelengths are incident on the photo cell. Examine the given figure and answer the following questions:

What is the effect on threshold frequency and stopping potential on increasing the frequency of incident beam of light? Justify your answer.

Light of wavelength 3500 Å is incident on two metals A and B. Which of them will yield photoelectrons, if their work functions are 4·2 eV and 1·9 eV respectively ? Make the necessary calculations to justify your answer.