Define Threshold frequency.

The work function of a material is 5.26 xx 10^-19J . Calculate its threshold frequency.

Photoelectric emission is observed from a metallic surface for frequencies v_(1) and v_(2) of the incident light rays (v_(1) gt v_(2)) . If the maximum values of kinetic energy of the photoelectrons emitted in the two cases are in the ratio of 1 : k , then the threshold frequency of the metallic surface is

The work function of caesium is 2.14 eV. Find the threshold frequency for caesium .

If the photoelectric work function of a metal is 5 eV, calculate the threshold frequency of the metal.

Light of frequency 4nu_0 is incident on the metal of the threshold frequency nu_0 . The maximum kinetic energy of the emitted photoelectric is

Light of frequency 1.5 times the threshold frequency is incident on a photo-sensitive material. If the frequency is halved and the intensity is doubled, the photoelectric current becomes