CBSE Class 12 Physics Competency-Based Questions With Answer Key 2024-25: Chapter 6 Dual Nature of Radiation and Matter FREE PDF Download

CBSE 2024-25 Competency-Based Questions With Answers: The Central Baord of Secondary Education has officially released the practice question paper for the academic year 2024-25, for the classes 10th  and 12th. Competency-focused questions can be helpful for students to secure good marks while referring and practicing them. It will help students to get familiar with the style and format of questions which are expected to appear in the final examinations.

The questions are designied chapter-wise for all the major subject of class 12th. In this article you will find specifically for Class 12 Physics Chapter 6 Dual Nature of Radiation and Matter, the CBSE Board has given the practice question paper for students to understand and up skill there preparation for 2025 examination. At the end of this article free PDF has been attached for the students to access and download. 

CBSE Class 12 Physics Chapter 6 Competency-Based Questions

Question 1: Select the correct statement regarding photoelectric emission. 

1. The  number  of  photoelectrons is  proportional  to  the  frequency  of  the light. 
2. The work function of the metal varies as a function of the depth from the surface. 
3. Photoelectrons are ejected from the metals only if the incident radiation has a certain minimum wavelength. 
4. The photoelectrons produced by a monochromatic incident light incident on the metal surface have a spread of kinetic energies. 

Question 2:  ASSERTION: A photon is different from a normal particle. 

REASON 1: Energy of the photon in motion is purely kinetic as it has no rest energy. REASON 2: A photon travels with the speed of light in vacuum. 

REASON 3: Energy  of  the  photon at  rest becomes purely  potential as its  rest mass is zero. Select the correct option. 

1. Assertion is correct. Only reason 3 is correct. 
2. Assertion is incorrect. Only Reason 2 is correct. 
3. Assertion is correct. Only reasons 1 and 2 are correct. 
4. Assertion is incorrect. Only Reasons 1 & 3 are correct. 

Question 3:  Light  from a source of  frequency  f >  fo  (threshold  frequency) is incident on a metal  surface.  If  the  intensity  of  incident  radiations  from  the  light  source  is increased  keeping  the  frequency  f  of  light  constant,  which  of  the  following quantities associated with emitted photoelectrons DOESNOT remain the same? 

1. only photoelectric current 
2. only de Broglie wavelength 
3. both momentum and maximum KE 
4. both de Broglie wavelength and the photo current

Question 4: Given are the maximum speeds of the photoelectrons corresponding to a 

wavelength of incident light on a certain metal surface. 

Wave length Maximum speed of the emitted electrons 

λ1 v1

λ2 v2

If v2 < v1, then, which of the following is/are CORRECT? 

1. Wavelength λ1 > Wavelength λ2
2. Frequency f1 < Frequency f2

III. Maximum KE due to wavelength λ1 > Maximum KE due to wavelength λ2

1. All are correct 
2. Only III is correct 
3. Only I and II are correct 
4. Only II and III are correct 

Question 5: Given are the work functions of two materials. 

A  radiation  of  wavelength  400  nm  is  made  to  fall  on  each  of  the  above  materials. In which of the two materials is the photoelectric emission observed?  Take h = 4.1 × 10‐15 eV‐s 

Question 6:  A light of wavelength 330 nm causes photoelectric emission  from a metal of  work  function  1  eV.  What  value  of  collector  potential  would  stop  the  photoemission? Take hc = 1240 eV‐ nm 

Question 7:  A light of wavelength 3000 Angstrom emits photoelectrons of maximum KE of  0.5 eV.  2  What will be the maximum KE of photoelectrons if the wavelength is changed  to 2000 Angstrom? Take hc = 12400 eV‐Å

Question 8: A powerful UV laser emits radiation of wavelength 300 nm with a power of 5  mW.  Determine  the  number  of  photons  of  this  beam  that  strikes  a  metal  surface every second. Take hc ~ 2 x 10‐16 J‐nm 

To access all the practice question of Physics Chapter 6 Dual Nature of Radiation and Matter, the complete FREE PDFs are attached here. Click on the 'Download PDF' to get the PDF.

Why Comptency Based Questions are Important ? 

Competency based questions are important because they help students to understandhow well they can prepare for the examinations. By practicing these question, students gain confidence and strength for the exam they are preparing. It encourages students to reflect on their achievements and understand their strength and weaknesses and also the area of improvements. 

Tips To Prepare For Board Exam 

Here are some tips which will help you to prepare for board exams: 

• Create a Study Plan: Make a study plan before exam will definitely help students. They can break the syllabus into sections and prepare for examinations. 

• Understand the Syllabus: Make sure you are familiar with the syllabus and topics which will be asked in your examinations.  
• Use Quality Study Materials: With NCERT or prescribed textbooks use additional reference books and guides for  ore and better understanding. 
• Practice Past Papers: Practice previous year sample papers just to get familiar withhow the questions will be asked and what will be the exam pattern. 
• Focus on Conceptual Understanding: Understand the concepts thoroughly rather than just memorising facts.
• Regular Revision: Regularly revise what you've studied to brushup your memory and make shorts notes for quick revision

By following these tips, you can improve your preparation for board exams and increase your chances of achieving your desired results.

Related:

• CBSE 2025 Board Exam Dates

• CBSE Class 12 Syllabus 2024-25 (ALL SUBJECT PDFS)

• CBSE Class 12 Exam Pattern and Marking Scheme 2024-2025

Also Check:

• NCERT Books for CBSE Class 12 - Latest Edition

• NCERT Solutions for CBSE Class 12 - Updated

• NCERT Rationalised Content for Class 12

• Video Courses For CBSE Class 12 Science

• Video Courses For CBSE Class 12 Commerce

• Video Courses For CBSE Class 12 Humanities