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State Einstein photoelectric equation. - Physics

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प्रश्न

State Einstein photoelectric equation. 

व्युत्पत्ती
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उत्तर

K.E.max = `(hν - phi_0)`

or K.E.max = (hν – hv0)     

or `1/2 mv_(max)^2 = hv - hv_0`

where, (K.E.)max → Maximum kinetic energy

= `1/2 mv_(max)^2`

`phi_0` Photoelectric work function = hv0

h → Planck’s constant

v → Frequency of radiation

v0 → Threshold frequency

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The Photoelectric Effect
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 14: Dual Nature Of Radiation And Matter - Short Answer II

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एससीईआरटी महाराष्ट्र Physics [English] 12 Standard HSC
पाठ 14 Dual Nature Of Radiation And Matter
Short Answer II | Q 1. (i)

संबंधित प्रश्‍न

If the frequency of incident light falling on a photosensitive material is doubled, then the kinetic energy of the emitted photoelectron will be ______.


Explain the inverse linear dependence of stopping potential on the incident wavelength in a photoelectric effect experiment.


The threshold wavelength of tungsten is 2.76 x 10-5 cm.
(a) Explain why no photoelectrons are emitted when the wavelength is more than 2.76 x 10-5 cm.
(b) What will be the maximum kinetic energy of electrons ejected in each of the following cases

(i) if ultraviolet radiation of wavelength λ = 1.80 × 10-5 cm and
(ii) radiation of frequency 4 x 1015 Hz is made incident on the tungsten surface?


Given the following data for incident wavelength and the stopping potential obtained from an experiment on the photoelectric effect, estimate the value of Planck's constant and the work function of the cathode material. What is the threshold frequency and corresponding wavelength? What is the most likely metal used for emitter?

Incident wavelength (in Å) 2536 3650
Stopping potential
(in V)
1.95 0.5

The minimum frequency for photoelectric effect on metal is 7 × 1014 Hz, Find the work function of the metal. 


Draw a neat labelled diagram of a schematic of the experimental setup for the photoelectric effect. 


With the help of a circuit diagram describing an experiment to study the photoelectric effect.


The following graph shows the stopping potential V0 versus frequency v for photoelectric emission from two metals A and B. The slope of each of the lines gives ______

 


The maximum velocity of the photoelectron emitted by the metal surface is 'v '. Charge and mass of the photoelectron is denoted by 'e' and 'm' respectively. The stopping potential in volt is ______.


When a light of wavelength 4000 Å falls on a photoelectric emitter, photoelectrons are liberated. For another emitter, light of wavelength 6000 Å is sufficient for photo emission. The work functions of the two emitters are in the ratio of ____________.


A metal surface is illuminated by light of given intensity and frequency to cause photoemission. If the intensity of illumination is reduced to one-fourth of its original value then the maximum KE of the emitted photoelectrons would be ______.


In photoelectric experiment, if both the intensity and frequency of the incident light are doubled, then the saturation of photoelectric current ______.


The threshold frequency for a certain photosensitive metal is v0. When it is illuminated by light of frequency v = 2v0, the maximum velocity of photoelectrons is v0. What will be the maximum velocity of the photoelectrons when the same metal is illuminated by light of frequency 

v = 5v0?


In photoelectric effect, for a light of different intensities but of same frequency, the stopping potential for a given metal is ____________.


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Following graphs show the variation of stopping potential corresponding to the frequency of incident radiation (F) for a given metal. The correct variation is shown in graph (v0 = Threshold frequency).


The photon of frequency vis incident on a metal surface whose threshold frequency is v0. The kinetic energy of the emitted photoelectrons will be ______.


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Which one of the following graphs represents the variation of photoelectric current (i) with intensity (I) of the incident light?


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(h = 6.63 × 10-34 Js, c = 3 × 108 ms-1)


When ultraviolet light of wavelength 100 nm is incident upon a sample of silver metal, a potential difference of 7.7 volt is required to stop the photoelectrons from reaching the collector plate. The potential required to stop photo electrons when light of wavelength 200 nm is incident upon silver is ______.


The maximum kinetic energy of the photoelectrons ejected will be ______ eV when the light of wavelength 350 nm is incident on a cesium surface. The work function of cesium = 1.9 eV.


For a given photosensitive material and frequency (> threshold frequency) of incident radiation, the photoelectric current varies with the intensity of incident light as:


If the maximum kinetic energy of emitted electrons in the photoelectric effect is 2eV, the stopping potential will be ______.


Explain the failure of wave theory of light to account for the observations from experiments on photoelectric effect.


Explain the formation of clouds at high altitude.


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