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When light of 470 nm falls on the surfac...

When light of 470 nm falls on the surface of potassium metal, electrons are emitted with a velocity of `6.4 xx 10^(4)ms^(-1)`. What is the minimum energy required to remove one moles electrons from potassium metal?

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To solve the problem of finding the minimum energy required to remove one mole of electrons from potassium metal when light of 470 nm falls on its surface, we can follow these steps: ### Step 1: Calculate the Kinetic Energy of the Emitted Electrons The kinetic energy (KE) of the emitted electrons can be calculated using the formula: \[ KE = \frac{1}{2} mv^2 \] where: ...
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When electromagnetic radiation of wavelength 300 nm falls on the surface of sodium, electrons are emitted with a kinetic energy of 1.68 xx 10^(5)J mol^(-1) . What is the minimum energy needed to remove an electron from sodium ? What is the maximum wavelength that will cause a photoelectron to be emitted?

When light with a wavelength of 400 nm falls on the surface of sodium , electrons with a kinetic energy of 1.05 xx 10^(5) " J mol"^(-1) are emitted . What is the minimum energy needed to remove an electron from sodium ?

Knowledge Check

  • If suitable light is allowed to fall on a clean metal surface, electrons are emitted from the surface. This phenomenon is called the photo - electric effect. Usually a radiation in the UV region and also in some cases in the visible region produces such an effect. The velocity and K.E. of the emitted electrons are measured by electric field . If wavelength of 470 nm falls on the surface of potassium metals, electrons are emitted with a velocity of 6.4 xx 10^(4) m sec^(-1) If bombarded light frequency is twice, then K.E. of emitted electrons is :

    A
    `1.86 xx 10^(-21) J`
    B
    `4.24 xx 10^(-19) J`
    C
    `1.98 xx 10^(-22)J`
    D
    `4.25 xx 10^(-22)J`

  • If suitable light is allowed to fall on a clean metal surface, electrons are emitted from the surface. This phenomenon is called the photo - electric effect. Usually a radiation in the UV region and also in some cases in the visible region produces such an effect. The velocity and K.E. of the emitted electrons are measured by electric field . If wavelength of 470 nm falls on the surface of potassium metals, electrons are emitted with a velocity of 6.4 xx 10^(4) m sec^(-1) The work function of potassium metal is :

    A
    `4.2 xx 10^(-19) J`
    B
    `1.86 xx 10^(-21) J`
    C
    `4.25 xx 10^(-30)J`
    D
    `4.2 xx 10^(-18)J`

  • If suitable light is allowed to fall on a clean metal surface, electrons are emitted from the surface. This phenomenon is called the photo - electric effect. Usually a radiation in the UV region and also in some cases in the visible region produces such an effect. The velocity and K.E. of the emitted electrons are measured by electric field . If wavelength of 470 nm falls on the surface of potassium metals, electrons are emitted with a velocity of 6.4 xx 10^(4) m sec^(-1) Stopping potential of given circuit is ,

    A
    `1.86 xx 10^(-21) J`
    B
    `18.6 xx 10^(-25) J`
    C
    `1.86 xx 10^(-23) J`
    D
    `1.86 xx 10^(-20)`

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    When electromagnetic radiation of wavelength 300 nm falls on the surface of sodium, electrons are emitted with kinetic energy of 1.68 xx 10^(5) J "ml"^(-1) . What is the minimum energy needed to remove an electron from sodium ? What is the maximum wavelength that will cause a photoelectron to be emitted.

    When electromagnetic radiaiton of wavelength 300 nm falls on the surface of sodium electrons are emitted with a kinetic enegry of 1.68xx10^(5)Jmol^(-) . What is the minimum enegry needed to remove an electorn from sodium? Strategy: The minimum enegry required to remove an electron from target metal is called work function W_(0) of the metal. It can be calculated from Eq., provided we know the energy of the incident photon and kinetic enegry of a single photoelectorn.

    A photon iof light with lambda = 470nm falls on a metal surface .As a result photoelectron are ejected with a velocity of 6.4 xx 10^(4) ms^(-1) .Find a. The kinetic energy of emited photonelectron b. The work function (in eV) of the metal surface

    When light with a wavelength of 400 nm falls on the surface of sodium , electrons with a kinetic energy of 1.05 xx 10^(5) " J mol"^(-1) are emitted . What is the maximum wavelength of light that will cause a photoelectron to be emitted ?

    When light falls on a metal surface , the maximum kinetic energy of the emitted photo - electrons depends upon

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