Dual Nature Of Radiation And Matter

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Light of two different frequencies whose photons
have energies 1 eV and 2.5 eV respectively, successively illuminate a metallic surface whose work function is 0.5 eV. Ratio of maximum speeds of emitted electrons will be

1 : 4

1 : 1

1 : 5

1 : 2

Solution

1 : 2

According to Einstein's photoelectric equation, the maximum kinetic energy of emitted photoelectrons is

K_max = h ν $- ϕ_{0}$

where hu is the energy of incident photon and $ϕ_{0}$ is the work function.

K_max = hv $- ϕ_{0}$

∴ $\frac{1}{2} {mv}_{\max}^{2}$ = hv $- ϕ_{0}$

As per question

$\frac{1}{2} {mv}_{\max}^{2}$ = 1eV $-$ 0.5 eV

= 0.5 eV ....(i)

and $\frac{1}{2} {mv}_{\max}^{2} = 2.5 eV - 0.5 eV$

= 2 eV ......(ii)

Dividing eqn. (i) by eqn. (ii), we get

$\frac{v_{\max_{1}}^{2}}{v_{\max_{2}}^{2}} = \frac{0.5 eV}{2 eV}$

= $\frac{1}{4}$

$\frac{v_{\max_{1}}}{v_{\max_{2}}} = \sqrt{\frac{1}{4}}$

$\frac{v_{\max_{1}}}{v_{\max_{2}}} = \frac{1}{2}$

Some More Questions From Dual Nature of Radiation and Matter Chapter

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Dual Nature Of Radiation And Matter

Light of two different frequencies whose photons
have energies 1 eV and 2.5 eV respectively, successively illuminate a metallic surface whose work function is 0.5 eV. Ratio of maximum speeds of emitted electrons will be

1 : 4

1 : 1

1 : 5

1 : 2

Some More Questions From Dual Nature of Radiation and Matter Chapter

The time by a photoelectron to come out after the photon strikes is approximately

An alpha nucleus of energy 1 /2 mv² bombards a heavy nuclear target of charge Ze. Then the distance of closest approach for the alpha nucleus will be proportional to

If I₀ is the intensity of the principal maximum in the single slit diffraction pattern, then what will be its intensity when the slit width is doubled?

The maximum number of possible interference maxima for slit-separation equal to twice the wavelength in Young’s double-slit experiment is

According to Einstein’s photoelectric equation, the plot of the kinetic energy of the emitted photo electrons from a metal Vs the frequency, of the incident radiation gives straight line whose slope

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For Daily Free Study Material Join wiredfaculty

Dual Nature Of Radiation And Matter

Light of two different frequencies whose photonshave energies 1 eV and 2.5 eV respectively, successively illuminate a metallic surface whose work function is 0.5 eV. Ratio of maximum speeds of emitted electrons will be 1 : 4 1 : 1 1 : 5 1 : 2

Some More Questions From Dual Nature of Radiation and Matter Chapter

The time by a photoelectron to come out after the photon strikes is approximately

An alpha nucleus of energy 1 /2 mv2 bombards a heavy nuclear target of charge Ze. Then the distance of closest approach for the alpha nucleus will be proportional to

If I0 is the intensity of the principal maximum in the single slit diffraction pattern, then what will be its intensity when the slit width is doubled?

The maximum number of possible interference maxima for slit-separation equal to twice the wavelength in Young’s double-slit experiment is

According to Einstein’s photoelectric equation, the plot of the kinetic energy of the emitted photo electrons from a metal Vs the frequency, of the incident radiation gives straight line whose slope

Mock Test Series

NCERT Sample Papers

Entrance Exams Preparation

Light of two different frequencies whose photons
have energies 1 eV and 2.5 eV respectively, successively illuminate a metallic surface whose work function is 0.5 eV. Ratio of maximum speeds of emitted electrons will be

1 : 4

1 : 1

1 : 5

1 : 2

An alpha nucleus of energy 1 /2 mv² bombards a heavy nuclear target of charge Ze. Then the distance of closest approach for the alpha nucleus will be proportional to

If I₀ is the intensity of the principal maximum in the single slit diffraction pattern, then what will be its intensity when the slit width is doubled?