text: Home Board Paper Solutions Text Book Solutions Articles NCERT Exemplar Solutions
  Question 2
  
  # The work function of caesium metal is 2.14 eV. When light of frequency 6 ×1014 Hz is incident on the metal surface, photoemission of electrons occurs. What is the(a) maximum kinetic energy of the emitted electrons,(b) Stopping potential, and(c) maximum speed of the emitted photoelectrons?
  
  Work function of caesium metal, ø0 = 2.14 eV
  
  Frequency of light, v = 6.0 x 1014 Hz
  
  (a) The maximum kinetic energy is given by the photoelectric effect as: K = hv - ø0
  
  Where,
  
  h = Planck’s constant = 6.626 × 10−34 Js
  
  ∴ K = 6.626 x 1034 x 6 x 1014 / 1.6 x 10-19 - 2.14 = 2.485 - 2.14 = 0.345 eV
  
  Hence, the maximum kinetic energy of the emitted electrons is 0.345 eV.
  
  ( b ) For stopping potential , V0 we can write the equation for kinetic energy as: K = eV0
  
  ∴ V0 = K/e = 0.345 x 1.6 x 10-19 / 1.6 x 10-19 = 0.345 V
  
  Hence, the stopping potential of the material is 0.345 V.
  
  (c) Maximum speed of the emitted photoelectrons = v
  
  Hence, the relation for kinetic energy can be written as: K = 1/2 mv2
  
  Where,
  
  m = Mass of an electron = 9.1 × 10−31 kg
  
  v2 = 2K/m = 2 x 0.345 x 1.6 x 10-19 / 9.1 x 10-31 = 0.1104 x 1012
  
  ∴ v = 3.323 x 105 m/s = 332.3 km/s
  
  Hence, the maximum speed of the emitted photoelectrons is 332.3 km/s.
  
  ## 3 Comment(s) on this Question
  
  #### Write a Comment:
  
  • NCERT Chapter
explanation: The provided text is a detailed solution to a physics problem related to the photoelectric effect. It contains a question and a corresponding answer. The question asks for the maximum kinetic energy of the emitted electrons, the stopping potential, and the maximum speed of the emitted photoelectrons when light of a specific frequency is incident on a caesium metal surface. The text provides a step-by-step solution to each part of the question.
distilabel_metadata.content: Evaluate the user given text extract and determine if it contains a math question and optionally and answer to this question.
  
  Output rules:
  
  1. Briefly describe the document and mention if it contains a question or a question and answer.
  2. Finalize the output with: Label: no-question,question,question-and-answer,multiple-question,multiple-question-and-answer
distilabel_metadata.role: system
distilabel_metadata.content: Home Board Paper Solutions Text Book Solutions Articles NCERT Exemplar Solutions
  Question 2
  
  # The work function of caesium metal is 2.14 eV. When light of frequency 6 ×1014 Hz is incident on the metal surface, photoemission of electrons occurs. What is the(a) maximum kinetic energy of the emitted electrons,(b) Stopping potential, and(c) maximum speed of the emitted photoelectrons?
  
  Work function of caesium metal, ø0 = 2.14 eV
  
  Frequency of light, v = 6.0 x 1014 Hz
  
  (a) The maximum kinetic energy is given by the photoelectric effect as: K = hv - ø0
  
  Where,
  
  h = Planck’s constant = 6.626 × 10−34 Js
  
  ∴ K = 6.626 x 1034 x 6 x 1014 / 1.6 x 10-19 - 2.14 = 2.485 - 2.14 = 0.345 eV
  
  Hence, the maximum kinetic energy of the emitted electrons is 0.345 eV.
  
  ( b ) For stopping potential , V0 we can write the equation for kinetic energy as: K = eV0
  
  ∴ V0 = K/e = 0.345 x 1.6 x 10-19 / 1.6 x 10-19 = 0.345 V
  
  Hence, the stopping potential of the material is 0.345 V.
  
  (c) Maximum speed of the emitted photoelectrons = v
  
  Hence, the relation for kinetic energy can be written as: K = 1/2 mv2
  
  Where,
  
  m = Mass of an electron = 9.1 × 10−31 kg
  
  v2 = 2K/m = 2 x 0.345 x 1.6 x 10-19 / 9.1 x 10-31 = 0.1104 x 1012
  
  ∴ v = 3.323 x 105 m/s = 332.3 km/s
  
  Hence, the maximum speed of the emitted photoelectrons is 332.3 km/s.
  
  ## 3 Comment(s) on this Question
  
  #### Write a Comment:
  
  • NCERT Chapter
distilabel_metadata.role: user
distilabel_metadata.raw_output_q_a_detector_0: The provided text is a detailed solution to a physics problem related to the photoelectric effect. It contains a question and a corresponding answer. The question asks for the maximum kinetic energy of the emitted electrons, the stopping potential, and the maximum speed of the emitted photoelectrons when light of a specific frequency is incident on a caesium metal surface. The text provides a step-by-step solution to each part of the question.
  
  Label: question-and-answer