Chapter 11: Dual Nature of Radiation and Matter Assertion Reason
These questions of two statements each, printed as Assertion and Reason. While answering these Questions you are required to choose any one of the following four responses.
(A) If both Assertion & Reason are true & the Reason is a correct explanation of the Assertion.
(B) If both Assertion and Reason are true but Reason is not a correct explanation of the Assertion.
(C) If Assertion is true but the Reason is false.
(D) If Assertion & Reason both are false.
Assertion-Reason Questions
- Assertion (A): Electrons exhibit wave-like behavior.
Reason (R): The de Broglie wavelength is associated with moving particles, including electrons.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The photoelectric effect demonstrates the particle nature of light.
Reason (R): The emission of electrons from a metal surface occurs only when the incident light has energy greater than the work function of the metal.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The kinetic energy of photoelectrons increases with the frequency of incident light.
Reason (R): The energy of incident photons is directly proportional to the frequency of light.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): Light exhibits both wave-like and particle-like properties.
Reason (R): Phenomena such as interference and diffraction demonstrate wave nature, while the photoelectric effect demonstrates particle nature.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The intensity of light affects the number of photoelectrons emitted in the photoelectric effect.
Reason (R): The number of incident photons increases with the intensity of light, resulting in more photoelectrons.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The stopping potential in a photoelectric experiment is independent of the intensity of incident light.
Reason (R): The stopping potential depends only on the frequency of the incident light and not on its intensity.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The de Broglie wavelength of a particle decreases as its momentum increases.
Reason (R): The de Broglie wavelength is inversely proportional to the momentum of the particle.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): Electrons produce diffraction patterns when passed through a crystal lattice.
Reason (R): The wavelength of electrons is comparable to the interatomic spacing in a crystal lattice.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The photoelectric effect is instantaneous.
Reason (R): The energy transfer from photons to electrons occurs without any noticeable time delay.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The energy of a photon is quantized.
Reason (R): Photons are discrete packets of energy called quanta, each with energy proportional to its frequency.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The Compton effect provides evidence for the particle nature of light.
Reason (R): In the Compton effect, photons collide with electrons, transferring energy and momentum as particles.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The wave function of a particle provides information about its probability density.
Reason (R): The square of the wave function’s magnitude gives the probability density of finding the particle at a given position.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The Heisenberg uncertainty principle states that the position and momentum of a particle cannot both be precisely known simultaneously.
Reason (R): Measuring one of these quantities to high precision disturbs the other, leading to inherent uncertainty.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): Electrons have both wave-like and particle-like properties.
Reason (R): Electrons can exhibit diffraction and interference, as well as photoelectric effect characteristics.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The photoelectric current increases with the increase in the intensity of incident light.
Reason (R): Higher intensity means more photons striking the metal surface, causing more electrons to be emitted.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The threshold frequency is the minimum frequency of light required to emit photoelectrons from a metal surface.
Reason (R): Below the threshold frequency, the energy of photons is insufficient to overcome the work function of the metal.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): Increasing the frequency of incident light increases the maximum kinetic energy of photoelectrons.
Reason (R): The energy of incident photons is directly proportional to their frequency, providing more energy to the emitted electrons.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The wave nature of particles is described by the de Broglie hypothesis.
Reason (R): According to de Broglie, every moving particle is associated with a wavelength given by λ = h/p.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The photoelectric effect supports the quantum theory of light.
Reason (R): The quantum theory explains the particle-like behavior of photons, including energy quantization and instantaneous energy transfer.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The wave-particle duality is a fundamental concept in quantum mechanics.
Reason (R): Particles such as electrons and photons exhibit both wave-like and particle-like properties, depending on the experimental conditions.
Answer: Both A and R are true and R is the correct explanation of A.