The energy of photoelectrons emitted from a sensitive plate is 1.56 eV. If its threshold old wavelength is `2500 Å`, calculate the wavelength of incident light.
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The threshold frequency `v_(0)` for a metal is `6xx10^(14) s^(-1)`. Calculate the kinetic energy of an electron emitted when radiation of frequency `v
`K.E.=1/2 m_(e)V^(2)=h(v-v_(0))` `:. K.E.=(6.626xx10^(-34))(1.1xx10^(15)-6xx10^(14))` `:. K.E.=(6.626xx10^(-34))(5xx10^(14))` `=3.313xx10^(-19) J`
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If a light with frequency `4xx10^(16) Hz` emitted photoelectrons with double the maximum kinetic as are emitted by the light of frequency `2.5xx10^(16
Correct Answer - `1xx10^(16) Hz` For frequency `2.5xx10^(16) Hz, h v=hv_(o)+KE_(max)` `:. h(2.5xx10^(16))=hv_(o)+KE_(max) ...(i)` For frequency `4xx10^(16)` Hz, `h(4xx10^(16))=hv_(o)+2KE_(max) ...(2)` Multiply `eq^(n)` (1) by `2` and substract `eq^(n)` (2) from it....
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The threshold wavelength `(lambda_(0))` of sodium metal is `6500 Å`. If UV light of wavelength `360 Å` is used, what will be kinetic energy of the pho
Correct Answer - 3 The threshold frequency `(v_(0))` corresponding to the wavelength `6500 Å` is `c//lambda_(0)` Therefore, the threshold energy `=hv_(0)hc//lambda_(0)` Substituting for `h, c` and `lambda_(0)` we gwt threshold energy...
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For silver metal, threshold frequency is `1.1 xx 10^(17) s^(-1)`. What is the maximum kinetic energy of the photoelectrons prodcued by shining ultravi
Correct Answer - A `E_("subjected")=hv_(0)+KE` `thereforeKE = 6.6 xx10^(-34)xx[(3xx10^(8))/(1.5 xx 10^(-9))-1.1xx10^(17)]` `= 5.94 xx10^(-17)J`
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You have to design a half-wave plate of quartz crystal for light of wavelength 5800Å. Calculate the thickness of the plate rquired for the purpose if
Correct Answer - `3.2xx10^(-5)`m
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A parallel - plate capacitor of plate area `A` and plate separation d is charged to a potential difference `V` and then the battery is disconnected .
Correct Answer - decrease in energy is `(1)/(2)(epsilon_(0)AV^(2))/(d)((epsilon_(r)-1)/(epsilon_(r)));` energy is transferred to the agent introducing the slab
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Between the plates of a parallel-plate capacitor there is a metallic plate whose thickness takes up `eta = 0.60` of the capacitor gap. When that plate
Correct Answer - (a)`-0.15mJ` (b) `0.15mJ`
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The photoelectric threshold wavelength for lithium is `8000 Å`. Find the maximum kinetic energy in eV of the emitted electrons from the surface by lig
Correct Answer - 0.5156 eV
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A parallel -plate capacitor with the plate area `100cm^2` and the separation between the plate `1.0cm` is connected across a battery of emf 24 volts .
Correct Answer - `2.5xx10^(-7)N`
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The energy of emitted photoelectrons depends up on
The energy of the emitted photoelectrons are directly proportional to the frequency of the incident radiation.
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