CBSE Class 12 Physics Answer Key 2025 PDF Download- OUT NOW

CBSE Class 12 Physics Answer Key 2025: The CBSE Class 12 Physics Answer Key 2025 will help students check their answers and estimate their scores for the Class 12 Physics Board Exam held on Today February 21, 2025. The answer key provides step-by-step solutions for all questions, helping students understand the correct approach to solving them. Whether you are looking for the class 12 physics answer key 2025 set 2, physics class 12 set 3 answer key 2025, or physics class 12 set 1 answer key 2025, we have covered all sets to ensure accuracy.

Students who appeared for the CBSE Today Class 12 Answer Key 2025 can use this guide to verify their responses and analyze their performance. The 2025 12th Physics Answer Key is designed to give a detailed explanation of each question from the Physics Class 12 CBSE Board Paper 2025 Solutions, making it easy for students to understand their mistakes and learn better for future exams. Stay tuned for the official and unofficial answer keys to cross-check your answers!

CBSE Class 12 Physics Exam Overview

CBSE Class 12 Physics Answer Key 2025 Set-wise Solutions

Physics Class 12  Question Paper 2025 Solutions are available for all three sets of question papers. Students can check their answers based on the respective set they received in the exam:

Each set has different questions or variations in numerical values, but the concepts remain the same. The answer key includes solutions for Multiple-Choice Questions (MCQs), Short Answer Questions (SA), and Long Answer Questions (LA).

Also check - CBSE Class 12 Physics Paper Analysis 2025

Physics Class 12 CBSE Paper 2025 Solutions – Section-wise Breakdown

The CBSE Class 12 Physics Board Exam 2025 was divided into different sections. Below is the detailed section-wise answer key:

1. Section A – MCQs and Very Short Answer Questions

This section contained one-mark questions, including conceptual MCQs, assertion-reasoning type questions, and very short descriptive answers.

• Example: If a question asked about the unit of resistivity, the correct answer would be ohm-meter (Ωm).
• The 2025 Physics Question Paper Answer Key helps students cross-check their answers and understand tricky conceptual questions.

2. Section B – Short Answer Questions (2 Marks Each)

This section had concept-based numerical and theoretical questions, such as derivations of basic formulas and reasoning-based problems.

• Example: State and explain Kirchhoff’s Law.

Answer: Kirchhoff’s Current Law (KCL) states that the sum of currents entering a junction equals the sum of currents leaving the junction. Kirchhoff’s Voltage Law (KVL) states that the total voltage around a closed loop is equal to the sum of voltage drops across components.

3. Section C – Long Answer Questions (3 Marks Each)

This section focused on numerical problems and derivations from key physics topics like optics, electromagnetism, and thermodynamics.

• Example: Derive the equation for the focal length of a convex lens using the lens formula.
• Answer: The lens formula is 1/f = 1/v - 1/u, where f is the focal length, v is the image distance, and u is the object distance. The derivation uses ray diagrams and sign conventions.

4. Section D – Case Study Questions (5 Marks Each)

This section introduced real-life application-based case studies, where students needed to analyze data and apply physics concepts.

• Example: A power transmission line carries 220V alternating current to a distant factory. Calculate the power loss if the resistance of the wires is 2Ω.
• The solution involves using P = I²R or P = V²/R formulas.

Difficulty Level & Student Reactions

Many students found the CBSE Class 12 Physics Board Exam 2025 to be of moderate difficulty, with a mix of conceptual, numerical, and derivation-based questions.

• The numerical questions required accurate calculations.
• Some students found the assertion-reasoning MCQs challenging.
• Many reported that optics and electromagnetism questions were tricky.

CBSE Class 12 Physics Important and Most Repeated Questions

Preparing for the CBSE Class 12 Physics Board Exam? Understanding the most important and frequently repeated questions can help you score better. Below is a well-structured list of crucial questions covering key topics like Electrostatics, Magnetism, Electromagnetic Induction, Modern Physics, and Optics. These questions, taken from past papers and commonly tested concepts, will help you strengthen your preparation and boost your confidence before the exam!"

Electric Charges and Fields

Q1. If the net electric flux through a closed surface is zero, then we can infer

• (a) E/4
• (b) 0
• (c) 2E
• (d) 4E
  (2022)

Q2. An electric dipole of length 2 cm is placed at an angle of 30° with an electric field 2 × 10⁵ N/C. If the dipole experiences a torque of 8 × 10⁻³ Nm, the magnitude of either charge of the dipole is:

• (a) 4μC
• (b) 7μC
• (c) 8mC
• (d) 2mC
  (2023)

Q3. Electric flux through a spherical surface shown in the figure is:
(2020)

Electrostatics and Conductors

Q4. Does the charge given to a metallic sphere depend on whether it is hollow or solid? Give reason for your answer. (Delhi 2017)

Q5. A uniformly charged large plane sheet has charge density
𝜎 = (1/18π) × 10⁻¹⁵ C/m²

Q6. N small conducting liquid droplets, each of radius r, are charged to a potential V each. These droplets coalesce to form a single large droplet without any charge leakage. Find the potential of the large drop. (2020)

Electric Potential and Equipotential Surfaces

Q7. Draw the equipotential surfaces corresponding to a uniform electric field in the z-direction.

Q8. Draw the equipotential surface due to an electric dipole.

Q9. Draw equipotential surface due to an isolated point charge (-q) and depict the electric field lines. (AI 2020)

Q10. A cube of side 20 cm is kept in a region as shown in the figure. An electric field E exists in the region such that the potential at a point is given by V = 10x + 5, where V is in volts and x is in meters. Find the electric field E and total electric flux through the cube. (AI 2020)

Semiconductors and Electronics

Q11. The energy required by an electron to jump the forbidden band in silicon at room temperature is about: (2023)

• (a) 0.01 eV
• (b) 0.5 eV
• (c) 0.7 eV
• (d) 1.1 eV

Q12. The ____, a property of materials C, Si, and Ge depends upon the energy gap between their conduction and valence bands. (2020)

Q13.Assertion (A): The resistance of an intrinsic semiconductor decreases with an increase in its temperature.
Reason (R): The number of conduction electrons as well as holes increases in an intrinsic semiconductor with a rise in temperature.

• (a) Both A and R are true, and R is the correct explanation of A.
• (b) Both A and R are true, but R is not the correct explanation of A.
• (c) A is true, but R is false.
• (d) A is false, but R is true. (2023)

Electromagnetic Induction and Alternating Current

Q14. A square-shaped coil of side 10 cm, having 100 turns, is placed perpendicular to a magnetic field which is increasing at 1 T/s. The induced emf in the coil is: (2023)

• (a) 0.1 V
• (b) 0.5 V
• (c) 0.75 V
• (d) 1.0 V

Q15. Two identical circular discs, one of copper and another of aluminum, are rotated about their geometrical axes with the same angular speed in the same magnetic field acting perpendicular to their planes. Compare:
(i) The induced emf
(ii) The induced current produced in discs between their center and edge. (2021C)

Q16. A flexible wire of irregular shape, abcd, as shown in the figure, turns into a circular shape when placed in a region of magnetic field directed normal to the plane of the loop. Predict the direction of the induced current in the wire.

Q17. A metallic rod PQ of length l is rotated with an angular velocity ω about an axis passing through its midpoint O, perpendicular to the plane of the paper, in a uniform magnetic field B, as shown in the figure. What is the potential difference developed between the two ends of the rod, P and Q? (2020)

Nuclear Physics and Atomic Structure

Q18. The ratio of the nuclear densities of two nuclei having mass numbers 64 and 125 is: (2023)

• (a) 64/125
• (b) ⅘
• (c) 5/4
• (d) 1

Q19. Which of the following statements is not correct according to the Rutherford model? (2020)

• (a) Most of the space inside an atom is empty.
• (b) The electrons revolve around the nucleus under the influence of the Coulomb force acting on them.
• (c) Most of the atom's mass and its positive charge are concentrated at its center.
• (d) The stability of the atom was established by the model.

Modern Physics and Wave-Optics

Q20. The energy of a photon of wavelength λ is: (2023)

• (a) hcλ
• (b) hc/λ
• (c) λ/hc
• (d) λh/c

Q21. Define the term threshold frequency in photoelectric emission. (2020)

Q22. Sodium light consists of two wavelengths, 5900Å and 5960Å. If a slit of width 2 × 10⁻⁴ m is illuminated by sodium light, find the separation between the first secondary maxima of the diffraction pattern of the two wavelengths on a screen placed 1.5 m away. (2019C)

Ray Optics and Mirrors

Q23. An object is kept 20 cm in front of a concave mirror with a radius of curvature of 60 cm. Find the nature and position of the image formed. (2020)

CBSE Class 12 Physics Answer Key 2025 – Official vs Unofficial Answer Key

• Students looking for CBSE Class 12 Physics Answer Key 2025 PDF Download can check coaching institute websites for unofficial solutions.
• The official CBSE Class 12 Physics Answer Key 2025 CBSE Board will be released on CBSE’s official website in March 2025.

How to Calculate Marks Using 12 Physics Answer Key 2025?

To estimate your score, follow these steps:

1. Match your answers with the correct responses in the 2025 Physics Question Paper Answer Key.
2. Allot marks as per the CBSE marking scheme:
   • Correct MCQ = 1 mark
   • Correct Short Answer = 2-3 marks
   • Correct Long Answer = Stepwise marks (up to 5 marks)
3. No negative marking, so total all correct answers to get the estimated score.

CBSE 12th Physics Answer Key 2025 – Expected Cutoff & Result Date

• The CBSE Class 12 Board Exam 2025 Results are expected to be announced in May 2025.
• Students can check their results on @cbseresults.nic.in.

Conclusion

The CBSE Class 12 Physics Answer Key 2025 is an essential tool for students to cross-check their answers and estimate their scores. Whether you are looking for Physics Class 12 CBSE Board Paper 2025 Solutions for Set 1, Set 2, or Set 3, this article provides complete details. Keep checking for official answer key updates on CBSE’s website.