Free Photons and the Particle Model of Light MCQs with Answers
196 Photons and the Particle Model of Light MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
The particle model treats light as photons with energy E equals hf and momentum related to wavelength. Questions involve the photoelectric effect, work function, threshold frequency, stopping potential and photon energy, while distinguishing particle behaviour from the wave description of interference and diffraction.
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196 questions · page 4 of 10
- A. Becomes double
- B. Becomes half
- C. remains same
- D. First increase then decrease
Explanation: The maximum energy of photoelectrons depends on the nature of metal surface and the frequency of incident light.
Correct answer: remains same- A. Sodium-Potassium
- B. Helium-Neon
- C. Carbon-oxygen
- D. Magnesium-Sodium
Explanation: Sodium or potassium cathode emits electrons for visible light. Cesium coated oxidized silver emits electrons for infrared light and some…
Correct answer: Sodium-Potassium- A. Compton Effect
- B. Annihilation
- C. Pair-production
- D. X-rays production
Explanation: In photoelectric effect the electrons are emitted from the metal surface when it is exposed to light, while in production of X-rays when…
Correct answer: X-rays production- A. Same
- B. Different
- C. Both A & B
- D. Independent of frequency of incident light
Explanation: The stopping potential, in the context of the photoelectric effect, refers to the minimum potential difference (voltage) required to…
Correct answer: Independent of frequency of incident light- A. Intensity of incident light
- B. Wavelength of incident light
- C. Energy of incident light
- D. Frequency of incident light
Explanation: In photoelectric effect electrons are emitted instantaneously; the intensity of light detemines only their numbers.
Correct answer: Intensity of incident light66. Which physical quantity will change if intensity of light falling on metal's surface is increased?
- A. K.E of photo electrons
- B. Plate potential
- C. Velocity of photo electron
- D. Current
Explanation: By increasing intensity of light, numbers of emitted electrons are increased. Hence current will be increased.
Correct answer: Current- A. Threshold frequency
- B. Work function
- C. Cut-off frequency
- D. Threshold energy
Explanation: The minimum amount of energy required to escape the electron from the metal surface is called work function "Φ".
Correct answer: Work function- A. Infinite rest mass
- B. No rest mass and no charge
- C. Rest mass but no change
- D. A. and B. are correct
Explanation: Photons are the bundles of energy are integral part of electromagnetic radiations and they could not be sub divided.
Correct answer: No rest mass and no charge- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: Explanation is given below in the attached image.
Correct answer: Option C- A. Frequency
- B. Brightness
- C. Intensity
- D. Power
Explanation: In photoelectric effect the electrons are emitted with different energies.
Correct answer: Frequency- A. Wave nature
- B. Both wave and particle nature
- C. Particle nature
- D. All of these
Explanation: The phenomenon of photoelectric effect cannot be explained if we assume that light consists of waves and energy is uniformly distributed…
Correct answer: Particle nature- A. Voe2
- B. Vo2e
- C. Voe
- D. work function
Explanation: The maximum energy of photoelectrons is:
Correct answer: Voe- A. the energy required to remove an electron from the sample
- B. the kinetic energy of the most energetic electron ejected
- C. the potential energy of the most energetic electron ejected
- D. the electric potential that causes the electron current to vanish
Explanation: The stopping potential is that retarding voltage for which the photoelectric current becomes zero. Even the electrons of maximum K.E.
Correct answer: the electric potential that causes the electron current to vanish- A. the energy of the least energetic electron before it is ejected
- B. the energy of the least energetic electron after it is ejected
- C. the energy of the most energetic electron before it is ejected
- D. the energy of the most energetic electron after it is ejected
Explanation: This fact shows that maximum K.E. of photoelectrons directly depends upon the frequency of light but independent of the intensity of light.
Correct answer: the energy of the most energetic electron after it is ejected- A. their kinetic energy
- B. the work function
- C. the number of photons that hit the sample
- D. the frequency of the incident light
Explanation: In photoelectric effect electrons are emitted instantaneously; the intensity (the number of Photons that hit the sample) of light…
Correct answer: the number of photons that hit the sample- A. frequency of the incident light
- B. intensity of the incident light
- C. time for which the light falls on the metal
- D. All of above
Explanation: In photoelectric effect electrons are emitted with different energies. The maximum energy of photoelectrons depends on the nature of metal…
Correct answer: frequency of the incident light- A. N ∝ L and E ∝ λ
- B. N ∝ L and E ∝ L
- C. N ∝ L and E ∝ 1/λ
- D. N ∝ 1/λ and E ∝ 1/L
Explanation: In photoelectric effect Electrons are emitted instantaneously; the intensity of light determines only their numbers.
Correct answer: N ∝ L and E ∝ 1/λ- A. intensity of light
- B. frequency of light
- C. work function of the metal
- D. Nature of material
Explanation: In photoelectric effect Electrons are emitted instantaneously; the intensity of light determines only their numbers. No.
Correct answer: intensity of light- A. kinetic energy
- B. potential energy
- C. binding energy
- D. thermal energy
Explanation: Energy of photon = work function + Max. K.E. of photoelectrons hf =Φ+ K.Emax
Correct answer: kinetic energy- A. directly proportional to
- B. inversely proportional to
- C. independent of
- D. directly proportional to square root of intensity
Explanation: Maximum K.E of photoelectrons ∝ Frequency of incident light
Correct answer: directly proportional to