Two stream of photons, possessing energies equal to twice and ten times the work function of metal are incident on the metal surface successively. The value of ratio of maximum velocities of the photoelectrons emitted in the two respective cases is x : y. The value of x is………

The work function of a metal is w0 and l is wavelength of incident radiation. There is no emission of photoelectron whenThe work function of a metal is w0 and l is wavelength of incident radiation. There is no emission of photoelectron when\

Photons with energy 5 eV are incident on a cathode C in a photoelectric cell. The maximum energy of emitted photoelectrons is 2 eV When photons of energy 6 eV are incident on C, no photoelectrons will reach the anode A, if the stopping potential of A relative to C is

In a photoelectric experiment, increasing the intensity of incident light:

The work functions of Caesium (Cs), Potassium (K) and Sodium (Na) are $2.14\mathrm{e}\mathrm{V},2.30\mathrm{e}\mathrm{V}$ and $2.75\mathrm{e}\mathrm{V}$ respectively. If incident electromagnetic radiation has an incident energy of $2.20\mathrm{e}\mathrm{V}$ , which of these photosensitive surfaces may emit photoelectrons?
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Given figure shows few data points in a photo electric effect experiment for a certain metal. The minimum energy for ejection of electron from its surface is: (Plancks constant ${}^{}$ )