Questions in Dual Nature of Radiation and Matter

Select	Question
	Assuming photoemission to take place, the factor by which the maximum velocity of the emitted photoelectrons changes when the wavelength of the incident radiation is increased four times, is
	Work function of a metal is 2.51 eV. Its threshold frequency is
	Energy conversion in a photoelectric cell takes place from
	Which one of the following is true in photoelectric emission
	When a point source of light is at a distance of one metre from a photo cell, the cut off voltage is found to be V. If the same source is placed at 2 m distance from photo cell, the cut off voltage will be
	The work function of a photoelectric material is 3.3 eV. The threshold frequency will be equal to
	If the work function of a metal is $'\varphi '$ and the frequency of the incident light is $'\nu '$, there is no emission of photoelectron if
	A photoelectric cell is illuminated by a point source of light 1 m away. When the source is shifted to 2 m then
	Light of wavelength $\lambda $strikes a photo-sensitive surface and electrons are ejected with kinetic energy E. If the kinetic energy is to be increased to 2E, the wavelength must be changed to $\lambda '$ where
	If in a photoelectric experiment, the wavelength of incident radiation is reduced from 6000 Å to 4000 Å then