NEET Physics: Dual Nature of Matter and Radiation Practice Questions
12 free multiple-choice questions on Dual Nature of Matter and Radiation for NEET Physics, each with the correct answer and a step-by-step explanation. Attempt a question, then reveal the solution to check your reasoning.
Practice thousands more Dual Nature of Matter and Radiation questions in the app →Q1. Which of the following statements correctly describes the relationship between the intensity of incident light and the kinetic energy of the emitted photoelectrons in the photoelectric effect?
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Correct answer: D — Intensity determines the number of photons striking the surface, which affects the number of emitted electrons.
The intensity of light affects the number of photons incident on the surface. However, once the threshold frequency is exceeded, the energy of each individual photon dictates the maximum kinetic energy (Kₘₐₓ), not the intensity.
Q2. Which concept fundamentally links the classical momentum of a particle to its associated wave property (matter wave)?
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Correct answer: C — Relationship between momentum and wavelength
The de Broglie relation establishes the direct link between the particle's classical momentum and the wave's characteristic wavelength.
Q3. In the photoelectric effect, if the frequency of incident light is exactly equal to the threshold frequency, what is the kinetic energy of the emitted photoelectrons?
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Correct answer: C — Zero
When the frequency of incident light is exactly equal to the threshold frequency (f₀), the minimum energy required for photoemission is supplied. In this specific case, the work function is entirely used to release the maximum kinetic energy of the emitted photoelectrons, resulting in a kinetic energy equal to the energy of the incident photon, Eₚₕₒₜₒₙ = hf₀, which equals hν (where ν is the threshold frequency).
Q4. Planck's constant (h) has what fundamental role in the theory of the photoelectric effect?
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Correct answer: B — It relates the energy of a photon to its frequency.
Planck's constant (h) is the proportionality constant that links the energy (E) of a photon to its frequency (f), making it central to the energy quantization in the photoelectric effect.
Q5. Which physical quantity is directly related to the de Broglie wavelength of a particle?
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Correct answer: A — Particle's momentum.
The de Broglie wavelength (λ) is inversely proportional to the momentum (p). Momentum is defined as p=mv, making momentum the most direct link to λ.
Q6. The minimum energy required to cause the emission of photoelectrons from a metal surface is known as the:
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Correct answer: C — work function
The minimum energy required to free an electron from a metal surface is defined as the work function (φ). This energy is necessary regardless of the frequency of the incident light (if φ is not supplied, no emission occurs).
Q7. In the photoelectric effect, the minimum frequency of incident radiation required to cause photoemission from a metal surface is known as:
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Correct answer: A — Threshold frequency
The threshold frequency (f₀) is the minimum frequency of incident light required to cause photoemission. Below this frequency, no photoemission occurs, regardless of the intensity of the light.
Q8. In the photoelectric effect, the energy of the incident photon is directly proportional to the frequency of the light. This relationship is based on which fundamental constant?
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Correct answer: A — Planck's constant
The relationship between the energy of a quantum of light (E) and its frequency (f) is given by E = hf, where h is Planck's constant.
Q9. What is the fundamental relationship described by Einstein's equation for the photoelectric effect?
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Correct answer: B — E = hf
The photoelectric effect is explained by the equation E = hf, where E is the energy of the photon, h is Planck's constant, and f is the frequency of the incident light.
Q10. Which of the following statements best describes the core implication of the de Broglie relation (λ= h/p) in the context of matter waves?
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Correct answer: C — Matter exhibits wave-like properties, meaning particles possess associated wavelengths, analogous to waves.
The de Broglie relation establishes the wave nature of matter. It implies that particles, which usually are viewed as point-like entities, also have an associated wavelength (λ), demonstrating their wave-particle duality.
Q11. In the photoelectric effect, if the energy of the incident photon is exactly equal to the work function of the metal, what will be the kinetic energy of the emitted photoelectrons?
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Correct answer: C — hν- φ
According to Einstein's photoelectric equation, E = hν= φ+ Kₘₐₓ, where Kₘₐₓ is the maximum kinetic energy of the emitted photoelectrons. If hν= φ, then Kₘₐₓ = 0. This means the emitted photoelectrons have zero kinetic energy (they just reach the threshold velocity).
Q12. If the frequency of incident light is less than the threshold frequency, what will happen in the photoelectric effect?
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Correct answer: D — No photoemission occurs
If the incident photon energy (hf) is less than the work function (φ), no photoemission occurs because the energy is insufficient.
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