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35 Cards in this Set
- Front
- Back
- 3rd side (hint)
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The electromagnetic _______ have dual Nature that is _______ nature and ________ nature. |
The electromagnetic radiation have dual Nature that is wave nature and particle nature |
1) for what ? 2) which are they ? |
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Define matter |
The wave associated particle nature is called matter |
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Define Photoelectric effect |
The phenomenon of emission electron from certain substance when it is expose to the radiation of suitable frequency is called photoelectric current |
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Draw the experimental setup for photoelectric effect |
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Draw the graph of photoelectric current with respect to frequency and write constant and variables |
Constant: Intensity, P.D, Nature Of E Variables: Frequency |
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Define Threshold Frequency |
The Minimum frequency of incident radiation for which the photoelectrons are just emitted from photosensitive material is called Threshold frequency. |
V not |
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What is Threshold frequency? And it's symbol and tell that is it different for different materials |
1] The wavelength corresponding to the threshold frequency is called Threshold wavelength. 2] Lambda not 3] Yes |
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In which case photoemission is possible? |
V is larger than V not & Lambda not is larger than Lambda |
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Draw the graph of photoelectric current with respect to intensity of light and write constant and variables |
Constant= frequency, P.D, Nature Variable= Intensity |
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Why the intensity of incident light is directly proportional to the photoelectric current |
When the intensity of incident light increases the emission of photo electrons are increased and therefore the photoelectric current is increases hence the intensity of incident light is directly proportional to the photoelectric current. |
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Draw graph for saturation current and write their constant and variable. |
Constant = frequency, intensity, material Variable = potential difference |
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Define Saturation Current |
If the positive potential of plate C increases from its minimum value then there is increase in a photoelectric current and it becomes maximum at particular value after that due increase the potential there is no increase photoelectric current this is called as saturation current |
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Draw the graph for stopping potential and write down the constant and variable |
Constant = frequency, intensity, material Variable = potential difference |
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Define stopping potential or cut off. |
The minimum negative potential applied to the plate C for which the photoelectric current become zero or stop is called stopping potential or cut off |
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Draw the graph when frequency and material is constant and potential difference and intensity is variable. |
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Explain why the maximum kinetic energy of emitted for photoelectron is independent on intensity |
If the incident beam of different intensity is incident on photo sensitive plate and the frequency is constant then for which we get the different values of saturation current but the same value of cut off from this we say that the maximum kinetic energy of emitted for photoelectron is independent on intensity. |
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Draw the graph when intensity and material is constant and variable is potential difference and frequency. |
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Explain why the maximum kinetic energy is depends on frequency of incident light |
If the incident beam of frequency and same intensity is incident on photosensitive plate then for which we get the same values of saturation current but the different values of cut off, hence the maximum kinetic energy is depends on frequency of incident light |
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Draw the graph of stopping potential with respect to incident frequency of different metal and write some explanation |
For different metals we have different values of Threshold frequency and also the work function the graph of stopping potential against frequency is straight line after Threshold frequency |
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Define photoelectric work function and write its unit |
The minimum energy required to remove the electron from the given photosensitive material is called photoelectric work function and which is measured in eV (1eV= 1.6×10^-19) |
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Write the Einstein's postulate of quantization of energy |
1] there is certain frequency called as Threshold frequency below which no photoemission is possible 2] the photoelectric current increases with increase in intensity of increase light 3] the maximum kinetic energy depends on frequency of incident radiation and its independent on intensity of incident 4] the energy is given by photon to the electron for remove its self there is no timeline between incidence of light and emission of electron |
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Write the Einstein's postulate of Photoelectric equation |
The light having the energy hv is incident on metal surface which is used in two parts that is ∅not is the energy or work function to remove the electron from surface at the remaining energy [hv-∅not] appears as an kinetic energy of emitted photoelectron therefore K.E.max = evnot K.E.max = hvnot-∅not evnot = hvnot-∅not ..... Einstein's photoelectric equation vnot = v h/e - ∅not/e From this equation we say that vnot valies linearly with incident frequency v and slope of straight line depends on constant he while intercept of line depends on material ∅not. K.E.max = 1/2 mv²max = hv - ∅not v=vnot therefore Kmax = 0 0 = hvnot - ∅not ∅not = hvnot |
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Write the failure of wave theory to explain the observation from experiment on photoelectric effect |
1] according to wave theory of light intensity of light watch major in terms of frequency to below the threshold frequency 2] Below the Threshold frequency no emission of electron |
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State Wave particle duality of electromagnetic radiation |
1] A Photon is the electromagnetic radiation of particular frequency having the same energy and momentum 2] The photons are electrically neutral so they can not deflected by electric or magnetic field 3] Photon have particle like collision like electron 4] In a photon particle collision energy and momentum get conserved but the number of photon can not be conserved |
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Draw the diagram of Photo cell and write some intro and application |
Intro = A photo cell is a device which converts a light energy into an electrical energy it works on the principle of Photoelectric effect. It consist of semicylindrical photosensitive metal plate E which is act as cathode and wire loop C which is act as anode an which is connected to microAmmeter Application = 1] optical sensor 2] Entry counter 3] Burclear Alarm
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Complete the black part |
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Fill the black part |
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Derive that |
It gives De-Broglies wavelength |
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Derive It |
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Use it as eqn 1 |
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By using which eqn we can find out the wavelength of electron if the potential difference is known |
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Draw the diagram of Davisson and Germer Experiment |
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Explain the Davisson and Germer experiment |
It consist of constant filament coated with barium oxide which is source of electron then this electron beam passing through collimating anode and its strike on nickel crystal from the nickel crystal it gets deflected and collected by movable detector whose next terminal is connected to the Galvanometer the whole assembly is in vacuum chamber and high tension is applied it. It's found at for deflected angle 50 degree and potential at 54 volt more electrons are collected. |
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Define wave particle [ duality of matter] |
The particle behaves like wave nature under the certain circumstances is called as wave particle. [Duality of matter] |
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When the wavelength associated with macroscopic particles do not play significant roles in our daily life? |
When the wavelength is negligible compare to the size of moving object as well as the width of path on which the object are moving therefore the wavelength associated with Macroscopic particles do not play significant roles in our daily life |
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Who plays significant roles in wavelength ? |
Electron is moving through small aperture of size 10^-10 m can plays significant roles in wavelength. |
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