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In a photo electric effects set-up, a po...

In a photo electric effects set-up, a point source of light of poewer `3.2xx10^(-3)` W emits mono energetic photons of energy 5.0 Ev. The source is located at a distance of 0.8m from the centre of a stationary metallic sphere of work function 3.0 Ev & of radius `8.0xx10^(6)`m. The efficiency of photo electric emission is one of every `10^(6)` incident photons. Assume that the sphere is isolated and initially neutral, and that photo electrons are instantly swept awy after emission.
(a) Calculate the number of photo electrons emitted.per second.
(b) Find the ratio of the wavelength of incident light to the de-Broglie wave length of the fastest photo electrons emitted. ltbr. (c) It is observed that the photo electron emission stops ata certain time tafter the light source is switched on. Why ?
(d) Evaluate the time t.

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In a photoelectric effect set up, a point source of light of power 3.2 xx10^(-3) W emits monoenergetic photons of energy 5eV .The source is located at a distance of a stationary metallic sphere of work function 3eV and radius 8xx10^(-3)m .The efficiency of photoelectron emission is one for every 10^(6) incident photons.Assume that the sphere is isolated and initially neutral and the photoelectrons are initially swept away after emission. Find the number of photons emitted per second

In a photoelectric effect set up, a point source of light of power 3.2 xx10^(-3) W emits monoenergetic photons of energy 5eV .The source is located at a distance of a stationary metallic sphere of work function 3eV and radius 8xx10^(-3)m .The efficiency of photoelectron emission is one for every 10^(6) incident photons.Assume that the sphere is isolated and initially neutral and the photoelectrons are initially swept away after emission. Find the maximum kinetic energy of photoelectrons:

In a photoelectric setup, a point source of light of power 3.2xx10^(-3) W emits monoenergetic photons of energy 5.0 eV. The source is located at a distance of 0.8 m from the center of a stationary metallic sphere of work function 3.0 eV and of radius 8.0xx10^(-3) m. The efficiency of photoelectron emission is 1 for every 10^(6) incident photons. Assume that the sphere is isolated and initially neutral and that photoelectrons are instantaneously swept away after emission. Q. It is observed that photoelectron emission stops at a certain time t after the light source is switched on. It is due to the retarding potential developed in the metallic sphere due to lift over positive charged. The stopping potential (V) can be represented as

in an experimental set up to study the photoelectric effect a point soure fo light of power 3.2xx10^(-3) W was taken. The source can emit monoenergetic photons of energy 5eV and is located at a distance of 0.8 m from the centre of a stationary metallic sphere of work-function 3.0 eV. The radius of the sphere is r = 8..10^(-3) m. The efficiency of photoelectric emission is one for every 10^6 incident photons. Based on the information given above answer the questions given below. (Assume that the sphere is isolated and photoelectrons are instantly swepts away after the emission). Time after which photoelectric emission stops is

in an experimental set up to study the photoelectric effect a point soure fo light of power 3.2xx10^(-3) W was taken. The source can emit monoenergetic photons of energy 5eV and is located at a distance of 0.8 m from the centre of a stationary metallic sphere of work-function 3.0 eV. The radius of the sphere is r = 8..10^(-3) m. The efficiency of photoelectric emission is one for every 10^6 incident photons. Based on the information given above answer the questions given below. (Assume that the sphere is isolated and photoelectrons are instantly swepts away after the emission). de-Broglie wavelength of the fastest moving photoelectron is

in an experimental set up to study the photoelectric effect a point soure fo light of power 3.2xx10^(-3) W was taken. The source can emit monoenergetic photons of energy 5eV and is located at a distance of 0.8 m from the centre of a stationary metallic sphere of work-function 3.0 eV. The radius of the sphere is r = 8..10^(-3) m. The efficiency of photoelectric emission is one for every 10^6 incident photons. Based on the information given above answer the questions given below. (Assume that the sphere is isolated and photoelectrons are instantly swepts away after the emission). It was observed that after some time emission of photoelectrons from the sphere stopped. Charge on the sphere when the photon emission stops is

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