Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main201912 Apr 2019Morning ShiftPhysicsDual Nature of MatterActual

The stopping potential V o (in volt) as a function of frequency ( v ) for a sodium emitter, is shown in the figure. The work function of sodium, form the data plotted in the figure, will be: (Given: Planck’s constant h = 6.63 × 10 - 34 J s , electron charge ( e ) = 1.6 × 10 - 19 C )

Options

  1. A2.12 e V
  2. B1.82 e V
  3. C1.95 e V
  4. D1.66 e V

Correct answer

D. 1.66 e V

Step-by-step solution

From Einstein's photoelectric equation, h ν = ϕ + e V 0     . ⇒ V 0 = h ν e - ϕ e     . . . . . . 1 At ν = 4 × 10 14   Hz , V 0 = 0 . Putting the value in equation 1 , we get 0 = hv e - ϕ e So, Work function ( ϕ ) = h ν e    i n   e V = 6.63 × 10 - 34 × 4 × 10 14 1.6 × 10 - 19 = 1.66   e V

Practice Dual Nature of Matter on Quantrex Academy →

More from Dual Nature of Matter

K₁ and K₂ be the maximum kinetic energies of photoelectrons emitted from a surface of a given material for the light of wavelength ₁ and ₂ , respectively. If ₁=2 ₂ then the work fu 2026The de Broglie wavelength for an electron accelerated through the potential difference of V₁ volt is ₁ . When the potential difference is changed to V₂ volt, the associated de Brog 2026Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): The electromagnetic wave exerts pressure on the surface on 2026An electron is travelling with a velocity v in free space and when it enters a medium, its velocity is reduced by 20 % . The de Broglie wavelength of electron in the medium is ₀ , 2026An electron of mass m is moving in an electric field E = -2E₀ i ( E₀ = constant > 0 ), with an initial velocity V = v₀ i ( v₀ = constant > 0 ). If ₀ = h 4mv₀ , its de Broglie wavel 2026Light source having wavelength 331 nm is used to generate photo-electrons whose stopping potential is 0.2 V. The work function of the used metal in the experiment is 10⁻¹⁹ J. The v 2026Match the List-I with List-II List-I List-II A. Planck's constant I. ML^2T⁻² B. Stopping potential II. T⁻¹ C. Work function III. ML^2T⁻¹ D. Threshold frequency IV. ML^2T⁻³A⁻¹ Choos 2026The de Broglie wavelength associated with an electron accelerated through a potential difference V is _e and the de Broglie wavelength associated with a proton accelerated through 2026 Full Dual Nature of Matter list All JEE Main PYQs