Let an electron requires 5×10^-19 joule energy to just escape from the irradiated metal. If photo electron is emitted after10^-9
s of the incident light, calculate the rate of absorption of energy. If this process is considered classically, the light energy is assumed to be continuously distributed over the wave front. Now, the electron can only absorb the light incident within a small area, say 10^-19 m² What is the intensity of illumination in order to see the photoelectric effect?

Work function of metal is 2 eV. Light of intensity 10^-5 W m^-2 is incident on 2 cm² area of it . If 10¹⁷ electron of these metals absorb the light, in how much time does the photo electric effect start ? Consider the waveform of incident light.

If the efficiency of an electric bulb of 1 watt is 10 %, what is the number of photons emitted by it in one second ? The wavelength of light emitted by it is 500 nm. (h=6.625×10^-34 J.s )

11×10¹¹ photons are incident on a surface in 10 s. These photons correspond to a wavelength of 10 Å. If the surface area of the given surface is 0.01 m² , the intensity of given radiation is ..... ( Velocity of light is 3×10⁸ ms^-1, h=6.625×10^-34 Js )

A beam of photons of intensity 2.5 W m^-2 each of energy 10.6 eV is incident on 1.0×10^-4 m² area of the surface having work function 5.2 eV. If 0.5% of incident photons emits photoelectrons, find the number of photons emitted in 1 s. Find minimum and maximum energy of these photo electrons. ( 1 eV= 1.6×10^-19 J )

Radius of a beam of radiation of wavelength 5000 Å is 10^-3 m . Power of the beam is 10^-3 W . This beam is normally incident on a metal of work function 1.9 eV. The charge emitted by the metal per unit area in unit time is ...... .Assume that each incident photon emits one electron. (h=6.625×10^-34 Js)

Work function of same metals are Na: 1.92 eV, K:2.2 eV, Cd:4.1 eV, Ni:5 eV, A laser beam from He-Cd of wavelength 3300 Å is incident on it. If it is brought to the distance of 10 cm. What will there be change in emission ? (h=6.625×10^-34 Js. c=3×10⁸ ms^-1, 1 eV= 1.6×10^-19 J )

U.V. light of wavelength 200 nm is incident on polished surface of Fe. Work function of the surface is 4.5 eV. Find, maximum speed of photo electrons. (h=6.625×10^-34 Js. c=3×10⁸ ms^-1 , 1 eV= 1.6×10^-19 J ) (m=9.11×10^-31 kg)

Light of 4560 Å of 1 mW is incident on photo-sensitive surface of Cs ( Cesium ) . If the quantum efficiency of the surface is 0.5%, what is the amount of photoelectric current produced?

Find the certainty with which one can locate the position of (1) a bullet of mass 25 g and (2) an electron, both moving with a speed 500 , accurate to 0.01%. Also, draw inferences based on your results. Mass of an electron is m_e= 9.1×10^-31 kg . Ratio of certainty obtained in measurement of its position will be ......