Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main201910 Apr 2019Morning ShiftPhysicsDual Nature of MatterActual

In a photoelectric effect experiment, the threshold wavelength of light is 380 n m . If the wavelength of incident light is 260 n m , the maximum kinetic energy of emitted electrons will be Given E (in e V ) = 1237 λ ( i n n m )

Options

  1. A4.5 e V
  2. B3.0 e V
  3. C1.5 e V
  4. D15.1 e V

Correct answer

C. 1.5 e V

Step-by-step solution

From Einstein’s photoelectric equation, K . E m a x = h c λ - h c λ 0 (here, λ 0 = threshold wavelength) = 1237 260 - 1237 380 = 1237 380 - 260 380 × 260 = 1.5 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