Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
MHT CET202619 April 2026Evening ShiftPhysicsDual Nature of MatterActual

When light of wavelength ' ' is incident on a photosensitive surface, the stopping potential is 'V'. When a light of wavelength 1.5 is incident on the same surface, the stopping potential is ' V 4 '. Threshold wavelength for the surface is

Options

  1. A6 5
  2. B7.5 4
  3. C7.5 9
  4. D9 5

Correct answer

D. 9 5

Step-by-step solution

Using Einstein's photoelectric equation: eV = hc - hc ₀ For the second case: e ( V 4 ) = hc 1.5 - hc ₀ Multiplying the second equation by 4 gives: eV = 4hc 1.5 - 4hc ₀ = 8hc 3 - 4hc ₀ Equating the two expressions for eV : hc - hc ₀ = 8hc 3 - 4hc ₀ Dividing by hc and rearranging the terms: 4 ₀ - 1 ₀ = 8 3 - 1 3 ₀ = 5 3 ₀ = 9 5 Answer: 9 5

Practice Dual Nature of Matter on Quantrex Academy →

More from Dual Nature of Matter

The basic principle used behind the working of electron microscope is: 2026The variation of the stopping potential ( V₀ ) with the frequency of incident radiation(n) is as given below. [ n₀ - threshold frequency. h- Planck's constant e- electronic charge] 2026When metal of work function 1.4eV is exposed to a radiation, the maximum kinetic energy of the electron emitted is 0.4eV. The stopping potential required is: 2026A monochromatic beam of photons of intensity to 1.5 Wm⁻² and energy 11.2 eV is incident on a material of work function 4.8 eV. What is the maximum speed of photoelectrons emitted d 2026What is the ratio of de Broglie wavelength of an electron to that of proton if the velocity of proton is 1 6 the velocity of electron? 2026Consider normal incidence of a monochromatic beam of photons of power P on a flat surface. Of the incident beam, 10% gets absorbed, 10% gets transmitted, and the rest is reflected 2026An experimental study of the photoelectric effect involves a metal of work function ₀ . What is the smallest wavelength of the incident photon to photoemit an electron of mass m wh 2026Work function of the metal is 2026 Full Dual Nature of Matter list All MHT CET PYQs