Photoelectric Emission

A : The process of photoelecton emission and thermionic emission of electrons is different . R : Photoelectric emission does not depend upon tempereature , whereas thermionic emission is temperature depandent .

represents a graph of most energetic photoelectrons K_(max) (in eV) and frequency v for a metal used as cathode in photoelectrons experiment. The threshold frequency of light for the photoelectric emission from the metal is

In a photoelectric emission, electrons are ejected from metals X and Y by light of frequency f. The potential difference V required to stop the electrons is measured for various frequencies.. If Y has a greater work function than X, which graph illustrates the expected results?

The work function of a metal is 2.5 xx 10^-19 J . (a) Find the threshold frequency for photoelectric emission. (b) If the metal is exposed to a light beam of frequency 6.0 xx 10^14 Hz, what will be the stopping potential ?

In a photoelectric emission, electrons are ejected from metals X and Y by light of frequency f. The potential difference V required to stop the electrons is measured for various frequencies.. If Y has a greater work function than X, which graph illustrates the expected results?

When a piece of metal is illuminated by monochromatic light of wavelength lambda, then stopping potential is 3V_(s) . When the same surface is illuminated by the light of wavelength 2lambda , then stopping potential becomes V_(s) . The value of threshold wavelength for photoelectric emission will be

Statement 1: In process of photoelectric emission, all emitted electrons do not have same kinetic energy. Statement 2: If radiation falling on photosensitive surface of a metal consists of different wavelengths, then energy acquired by electrons absorbing photons of different wavelengths shall be different.

When a certain photosensistive surface is illuminated with monochromatic light of frequency v, the stopping potential for the photo current is V_(0)//2 . When the surface is illuminated by monochromatic light of frequency v//2 , the stopping potential is V_(0) . The threshold frequency gor photoelectric emission is :

In a series of photoelectric emission experiments on a certain metal surface, possible relationships between the following quantities were investigated: threshold frequency f_0 , frequency of incident light f, light intensity P, photocurrent I, maximum kinetic energy of photoelectrons T_(max) . Two of these quantities, when plotted as a graph of y against x, give a straight line through the origin. Which of the following correctly identifies x and y with the photoelectric quantities ?

The work function for the following metals is given Na: 2.75 eV, K:2.30 eV , Mo: 4.17 eV , Ni: 515 eV. Which of these metals will not give photoelectric emission for a radiation of wavelength 3300 A from a He-Cd laser placed 1m away from the photocell? What happens if the laser is brought nearer and placed 50 cm away?