The photoelectric threshold wavelength for lithium is `8000 Å`. Find the maximum kinetic energy in eV of the emitted electrons from the surface by light of wavelength `6000 Å`. Take `h=6.6 xx 10^(-34) Js`.
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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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When photons of wavelength `lambda_(1) = 2920 Å` strike the surface of metal A, the ejected photoelectron have maximum kinetic energy of `k_(1) eV` an
Correct Answer - (a) `phi_(A) = 2.25 eV, phi_(B) = 4.2 eV` (b) `2e V`
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Find the number of photons emitted per second by a 25 W source of monochromatic light of wavelength `6600 Å`. What is the photoelectric current assumi
Correct Answer - `8.33 xx 10^(19), 0.4 A`
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Photoelectric work function for a surface is 2.4 eV. Light of wavelength `6.8 xx 10^(-7)`m shines on the surface. Find the frequency of incident light
Correct Answer - `v =4.41 xx 10^(14)Hz,v_(0)=5.82 xx 10^(14) Hz`, no photoelectric emission occurs as `v lt v_(0)`
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Calculate the kinetic energy of a photoelectron (in eV) emitted on shining light of wavelength `6.2 xx 10^(-6)m` on a metal surface. The work function
Correct Answer - 0.1 eV
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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 incid
Correct Answer - `1379 Å`
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The photoelectric threshold wavelength for tungsten is `2400 Å`. Determine the energy of the electrons ejected from its surface when exposed to ultrav
Correct Answer - 1.48 eV
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