Home
Class 12
CHEMISTRY
Calculate the threshold freqency of th...

Calculate the threshold freqency of the metalfrom the photoelectronsare emitted with zero velocity when exposed to radiation of wavelength 6800 `Å`
Hint `: KE = (1)/(2) mv^(2)`
`hv= hv_(0) + KE, KE=0`
`v= (c ) /( lambda)`

Text Solution

Verified by Experts

`4.41 xx 10^(14) s^(-1)`
Promotional Banner

Topper's Solved these Questions

  • STRUCTURE OF ATOM

    AAKASH INSTITUTE|Exercise ASSIGNMENT ( SECTION -A) Objective Type Questions (One option is correct)|47 Videos

  • STRUCTURE OF ATOM

    AAKASH INSTITUTE|Exercise ASSIGNMENT ( SECTION -B) Objective Type Questions (One option is correct)|38 Videos

  • STRUCTURE OF ATOM

    AAKASH INSTITUTE|Exercise illustration 2|1 Videos

  • STRUCTURE OF ATOM

    AAKASH INSTITUTE|Exercise ASSIGNMENT (SECTION -D) Assertion-Reason Type Questions|15 Videos

  • SURFACE CHEMISTRY

    AAKASH INSTITUTE|Exercise Assignment Section - C (Assertion - Reason type questions)|10 Videos

Similar Questions

Explore conceptually related problems

The threshold wavelength for a metal is 5000 Å . The maximum K.E. of the photoelectrons emitted when ultraviolet ligh of wavelength 2500 Å falls on it is

Electrons are emitted with zero velocity from a metal surface when it is exposed to radiation of wavelength 6800 Å . Calculate threshold frequency ( v_0) and work function (W_0) of the metal.

Calculate the frequency of paritcle wave, when the kinetic energy of a sub-atomic particle is 3.79 xx 10^(-27) J . Hint : KE = (1)/(2) mv^(2) lambda = (h)/(mv) , lambda = ( v)/( v) :. (v)/(v) = (h)/( mv), v= (mv^(2))/( h) = ( 2 xx ( 1)/(2) mv^(2))/( h)

The maximum K.E. of photoelectrons ejected from a photometer when it is irradiated with radiation of a wavelength 400nm is 1eV. If the threshold energy of the suface is 1.9 eV,

If lambda_0 is the Threshold wavelength of a metal for photoelencron emisssion . If the metal is exposed to the light of wavelngth lambda then the velocity of ejectred electgron will be sqrt ((2h)/m ( lambda_0 - lambda) K ) . The value fo (K) is :

The emission of electrons from a metal surface exposed rto light radaition of appropriate wavelength is called photoelectroic effect .The emmited electron are called photo=-weklectron work function of threshold energy may be defined as the minimum amount of energy required to ejercted electron from a most surface .According to Einstein Maximum kinetic energy of ejected electron = Aborbed energy - Work function (1)/(2) mv_(max)^(2) = h(v) - h(v_(n)) = hv [(1)/(lambda) -0 (1)/(lambda_(n))] Where v_(n) and lambda_(0) are thereshold frequency and threshold wavelength respectively Sopping potential : it is the miximum potential at which the photoelectric current becomes zero if V_(0) is the stopping potential eV_(0) = h(v- v_(0)) Whaich of the following is the graph between the frequency (V) of the incident radiation and the stopping potential (v) ?

The emission of electrons from a metal surface exposed rto light radaition of appropriate wavelength is called photoelectroic effect .The emmited electron are called photo=-weklectron work function of threshold energy may be defined as the minimum amount of energy required to ejercted electron from a most surface .According to Einstein Maximum kinetic energy of ejected electron = Aborbed energy - Work function (1)/(2) mv_(max)^(2) = h(v) - h(v_(n)) = hv [(1)/(lambda) - (1)/(lambda_(n))] Where v_(n) and lambda_(0) are thereshold frequency and threshold wavelength respectively Sopping potential : it is the miximum potential at which the photoelectric current becomes zero if V_(0) is the stopping potential eV_(0) = h(v- v_(0)) In the photoelectric currect effect the shape of strainght line graph between stopping potential (V_(0)) and frequency of incident light (V) gves

AAKASH INSTITUTE-STRUCTURE OF ATOM -Try Yourself
  1. the threashold frequency v(0) for a metal is 7xx10^(14)s^(-1) . Calcul...

    Text Solution

    |

  2. Photoelectrons are removed with kinetic energy 1.864 xx 10^(-21)J, wh...

    Text Solution

    |

  3. Calculate the threshold freqency of the metalfrom the photoelectrons...

    Text Solution

    |

  4. Calculate the energy associated with the first orbitof He^(+).What is ...

    Text Solution

    |

  5. what are the frequency and wavelength of a photon emitted during a tra...

    Text Solution

    |

  6. Calculate the ratio of the radius of 1^(st) orbit of H atom to thatof4...

    Text Solution

    |

  7. Calculate thevelocity of the electron in the third orbit of hydrogen ...

    Text Solution

    |

  8. what will be the wavelength of a ball of mass 0.1 kg moving with a vel...

    Text Solution

    |

  9. Calcualte the wavelength of matter wave associated with small ball of...

    Text Solution

    |

  10. A beam of helium atoms moves with a velocity of2 xx 10^(4) ms^(-1). Fi...

    Text Solution

    |

  11. Calculate the frequency of paritcle wave, when the kinetic energy of a...

    Text Solution

    |

  12. Calculate the uncertainty in the position of a dust particle with m...

    Text Solution

    |

  13. A microscope using suitable photons is employed to locate an electron...

    Text Solution

    |

  14. A golf ball has a mass of 40g and a speed of 45m//s. If the speed can ...

    Text Solution

    |

  15. What is the uncertainty in velocity of an electron if the uncertainty ...

    Text Solution

    |

  16. Calculate the uncertainty in the velocity of a wagon of mass 3000 kg, ...

    Text Solution

    |

  17. An electron has a speed3 xx 10^(3) ms^(-1) with uncertainty 0.07 % . W...

    Text Solution

    |

  18. Usings,p,d,f notations, describe the orbital with the following quant...

    Text Solution

    |

  19. What is the toal number of orbitals associated with the principal quan...

    Text Solution

    |

  20. Which of the following orbitals are possible ? 1pm, 2s, 3f, 3d

    Text Solution

    |