JKBOSE Class 12 Physics Question Paper 2026 with Answers PDF
Introduction
Students preparing for the Jammu and Kashmir Board of School Education (JKBOSE) Class 12 Physics examination can use this page to practise important concepts, numerical problems and theoretical questions. This resource includes an original Physics practice question paper for 2026, along with an answer key and step-by-step solutions to help students check their preparation.
The paper covers major Class 12 Physics topics, including electrostatics, current electricity, magnetism, electromagnetic induction, alternating current, optics, dual nature of radiation and matter, atoms, nuclei and semiconductor electronics. Students should compare these topics with the official syllabus applicable to their examination session.
Important: This is an independently prepared practice paper, not a verbatim copy of the actual JKBOSE 2026 examination paper. The marks distribution and time limit below are illustrative. Check the official board documents for the exact examination pattern.
JKBOSE Class 12 Physics Paper 2026: Overview
| Detail | Information |
|---|---|
| Board | Jammu and Kashmir Board of School Education |
| Class | 12th |
| Subject | Physics |
| Session | 2026 |
| Resource | Original Practice Question Paper |
| Theory practice marks | 70 |
| Suggested time | 3 hours |
| Answers | Included |
| Format | Questions, answer key and solutions |
JKBOSE Class 12 Physics Question Paper 2026
Class: 12th
Subject: Physics
Time: 3 Hours
Maximum Marks: 70
General Instructions
- Attempt all questions according to the instructions given in each section.
- Write the appropriate SI units with numerical answers.
- Draw neat, labelled diagrams wherever required.
- Show the necessary steps in numerical problems.
- The question paper is intended for practice and does not reproduce the official 2026 paper.
Section A: Multiple-Choice Questions
10 × 1 = 10 marks
Q1. The SI unit of electric field is:
(a) Coulomb
(b) Newton per coulomb
(c) Joule per coulomb
(d) Ohm
Q2. The electric potential at a distance (r) from a point charge (Q) in vacuum is:
(a) (\frac{kQ}{r})
(b) (\frac{kQ}{r^2})
(c) (kQr)
(d) (\frac{kr}{Q})
Q3. The SI unit of capacitance is:
(a) Tesla
(b) Weber
(c) Farad
(d) Henry
Q4. Ohm’s law is expressed as:
(a) (V=IR)
(b) (V=I/R)
(c) (R=VI)
(d) (I=VR)
Q5. The magnetic force on a stationary charged particle in a magnetic field is:
(a) Maximum
(b) Minimum but non-zero
(c) Zero
(d) Infinite
Q6. The SI unit of magnetic flux is:
(a) Tesla
(b) Weber
(c) Henry
(d) Ampere
Q7. The phenomenon responsible for the production of an induced emf due to changing magnetic flux is:
(a) Polarisation
(b) Electromagnetic induction
(c) Interference
(d) Diffraction
Q8. The power factor of a purely resistive AC circuit is:
(a) Zero
(b) 0.5
(c) One
(d) Infinite
Q9. The photoelectric effect supports the:
(a) Wave nature of light only
(b) Particle nature of light
(c) Magnetic nature of light
(d) Nuclear nature of light
Q10. A p-type semiconductor is formed by doping pure silicon with:
(a) A pentavalent impurity
(b) A trivalent impurity
(c) A noble gas
(d) A radioactive element
Section B: Very Short-Answer Questions
7 × 2 = 14 marks
Q11. State Coulomb’s law and write its mathematical expression.
Q12. Define electric dipole moment and state its SI unit.
Q13. What is drift velocity? Write the relation between electric current and drift velocity.
Q14. State Kirchhoff’s two laws of electrical circuits.
Q15. What is electromagnetic induction? State Faraday’s law.
Q16. Define the work function of a metal. What is its SI unit?
Q17. Write any two differences between intrinsic and extrinsic semiconductors.
Section C: Short-Answer and Numerical Questions
7 × 3 = 21 marks
Q18. Two point charges of (2,\mu C) and (3,\mu C) are separated by a distance of (0.3,m) in vacuum. Calculate the magnitude of the electrostatic force between them. Take (k=9\times10^9,Nm^2/C^2).
Q19. A resistor of (6,\Omega) is connected across a (12,V) battery. Calculate the current through the resistor and the power consumed.
Q20. Explain the principle of a potentiometer. State one advantage of a potentiometer over a voltmeter.
Q21. A coil of 100 turns experiences a change in magnetic flux per turn from (0.02,Wb) to zero in (0.1,s). Calculate the magnitude of the average induced emf.
Q22. Explain the conditions required for sustained interference of light. What is meant by coherent sources?
Q23. Light of wavelength (400,nm) falls on a metal with work function (2,eV). Calculate the maximum kinetic energy of the emitted photoelectrons. Use (hc=1240,eV,nm).
Q24. The half-life of a radioactive substance is 10 days. What fraction of the original sample remains after 30 days? Explain your calculation.
Section D: Long-Answer Questions
5 × 5 = 25 marks
Q25. Derive the expression for the equivalent capacitance of two capacitors connected in series. If (C_1=3,\mu F) and (C_2=6,\mu F), calculate their equivalent capacitance.
Q26. State Kirchhoff’s laws and explain how they can be used to solve electrical circuits. Include the physical principle behind each law.
Q27. Explain the principle and working of a transformer. Write the turns ratio relation for an ideal transformer and mention two causes of energy loss in a practical transformer.
Q28. Derive the lens formula for a thin lens using the standard Cartesian sign convention. Also define the power of a lens and state its SI unit.
Q29. Explain the working of a p-n junction diode under forward and reverse bias. Draw or describe its current-voltage characteristics and identify the region in which it conducts appreciable forward current.
JKBOSE Class 12 Physics Question Paper 2026: Answer Key
Section A: MCQ Answers
| Question | Correct Answer |
|---|---|
| Q1 | (b) Newton per coulomb |
| Q2 | (a) (kQ/r) |
| Q3 | (c) Farad |
| Q4 | (a) (V=IR) |
| Q5 | (c) Zero |
| Q6 | (b) Weber |
| Q7 | (b) Electromagnetic induction |
| Q8 | (c) One |
| Q9 | (b) Particle nature of light |
| Q10 | (b) A trivalent impurity |
Section B: Answers
Q11. Coulomb’s law
Coulomb’s law states that the electrostatic force between two stationary point charges is directly proportional to the product of their charges and inversely proportional to the square of the distance between them.
[ F=k\frac{|q_1q_2|}{r^2} ]
In vacuum, (k=1/(4\pi\varepsilon_0)). Like charges repel and unlike charges attract.
Q12. Electric dipole moment
Electric dipole moment is the product of the magnitude of either charge and the separation vector directed from the negative charge to the positive charge.
[ \vec p=q\vec d ]
Its SI unit is coulomb-metre ((C,m)).
Q13. Drift velocity
Drift velocity is the average velocity acquired by charge carriers in a conductor due to an applied electric field.
[ I=nqAv_d ]
Here, (n) is the carrier number density, (q) is the magnitude of charge, (A) is the cross-sectional area and (v_d) is the magnitude of drift velocity.
Q14. Kirchhoff’s laws
- Junction law: The algebraic sum of currents at a junction is zero. It follows from conservation of electric charge.
- Loop law: The algebraic sum of potential differences around a closed loop is zero. It follows from conservation of energy.
Q15. Electromagnetic induction
Electromagnetic induction is the production of an emf when the magnetic flux linked with a circuit changes.
Faraday’s law is:
[ \varepsilon=-N\frac{d\Phi_B}{dt} ]
The negative sign represents Lenz’s law.
Q16. Work function
The work function is the minimum energy needed to remove an electron from the surface of a metal.
Its SI unit is the joule ((J)); it is also commonly expressed in electronvolts ((eV)).
Q17. Intrinsic and extrinsic semiconductors
| Intrinsic semiconductor | Extrinsic semiconductor |
|---|---|
| Pure semiconductor without intentional doping | Semiconductor doped with a suitable impurity |
| Electron and hole concentrations are equal at thermal equilibrium | Electron and hole concentrations are generally unequal |
Section C: Solutions
Q18. Electrostatic force
Given:
[ q_1=2\times10^{-6}C ]
[ q_2=3\times10^{-6}C,\quad r=0.3m ]
Using Coulomb’s law:
[ F=9\times10^9 \frac{(2\times10^{-6})(3\times10^{-6})}{(0.3)^2} ]
[ F=\frac{0.054}{0.09}=0.6N ]
Answer: (0.6,N). The force is repulsive because both charges are positive.
Q19. Current and power
Given (V=12V) and (R=6\Omega).
Using Ohm’s law:
[ I=\frac{V}{R}=\frac{12}{6}=2A ]
Power consumed:
[ P=VI=12\times2=24W ]
Answers: Current (=2A); power (=24W).
Q20. Potentiometer
A potentiometer works on the principle that the potential drop along a uniform wire carrying a steady current is proportional to its length.
At the balance point, no current flows through the galvanometer branch.
One advantage is that a potentiometer can measure emf without drawing current from the source at the balance point, making it more accurate for emf measurement than an ordinary voltmeter.
Q21. Induced emf
Given:
- Number of turns (N=100)
- Initial flux per turn (=0.02Wb)
- Final flux per turn (=0)
- Time (=0.1s)
Using Faraday’s law:
[ |\varepsilon|=N\frac{|\Delta\Phi|}{\Delta t} ]
[ |\varepsilon|=100\times\frac{0.02}{0.1} ]
[ |\varepsilon|=20V ]
Answer: (20V).
Q22. Sustained interference
Sustained interference requires two coherent light sources with the same frequency and a constant phase difference. The waves must overlap, and their polarisations should be compatible.
Coherent sources are sources that emit waves of the same frequency with a fixed phase difference.
Q23. Photoelectric effect
Given:
[ \lambda=400nm,\quad \phi=2eV ]
Photon energy:
[ E=\frac{hc}{\lambda}=\frac{1240}{400}=3.1eV ]
Einstein’s photoelectric equation:
[ K_{\max}=E-\phi ]
[ K_{\max}=3.1-2=1.1eV ]
Answer: (1.1eV), or approximately (1.76\times10^{-19}J).
Q24. Radioactive decay
Half-life (T_{1/2}=10) days.
Elapsed time (t=30) days.
Number of half-lives:
[ n=\frac{t}{T_{1/2}}=\frac{30}{10}=3 ]
Remaining fraction:
[ \frac{N}{N_0}=\left(\frac12\right)^3=\frac18 ]
Answer: One-eighth of the original sample, or (12.5%), remains.
Section D: Long-Answer Solutions
Q25. Capacitors in series
For capacitors connected in series, the charge (Q) on each capacitor has the same magnitude, while the total potential difference is the sum of individual potential differences.
[ V=V_1+V_2 ]
Using (V=Q/C):
[ \frac{Q}{C_{\mathrm{eq}}}=\frac{Q}{C_1}+\frac{Q}{C_2} ]
Therefore,
[ \frac1{C_{\mathrm{eq}}}=\frac1{C_1}+\frac1{C_2} ]
For two capacitors:
[ C_{\mathrm{eq}}=\frac{C_1C_2}{C_1+C_2} ]
Substituting (C_1=3\mu F) and (C_2=6\mu F):
[ C_{\mathrm{eq}}=\frac{3\times6}{3+6} =\frac{18}{9}=2\mu F ]
Answer: (2\mu F).
Q26. Kirchhoff’s laws and their use
Kirchhoff’s junction law states that the algebraic sum of currents entering and leaving a junction is zero:
[ \sum I=0 ]
This follows from conservation of electric charge.
Kirchhoff’s loop law states that the algebraic sum of potential differences around a closed loop is zero:
[ \sum \Delta V=0 ]
This follows from conservation of energy.
To solve a circuit, assign current directions, apply the junction law at the relevant junctions and apply the loop law to independent closed loops. Solve the resulting simultaneous equations to find unknown currents and potential differences. A negative calculated current means the actual current flows opposite to the assumed direction.
Q27. Transformer
A transformer is a device that increases or decreases alternating voltage using mutual induction between two coils wound around a common magnetic core.
When alternating current flows through the primary coil, it produces a changing magnetic flux in the core. This changing flux links the secondary coil and induces an emf in it.
For an ideal transformer:
[ \frac{V_s}{V_p}=\frac{N_s}{N_p} ]
Here, (V_p) and (V_s) are the primary and secondary voltages, and (N_p) and (N_s) are their respective turns.
- If (N_s>N_p), it is a step-up transformer.
- If (N_s<N_p), it is a step-down transformer.
Two causes of energy loss are eddy currents in the core and hysteresis in the magnetic material. Winding resistance also causes copper losses.
Q28. Thin lens formula and power
For a thin lens, using the Cartesian sign convention, the standard lens formula is:
[ \frac1f=\frac1v-\frac1u ]
Here, (f) is focal length, (u) is object distance and (v) is image distance. Distances are measured from the optical centre with signs assigned according to the Cartesian convention.
The formula follows from the geometry of rays passing through a thin lens and the similarity of the relevant triangles formed by the object, image and principal axis.
The power of a lens is the reciprocal of its focal length measured in metres:
[ P=\frac1f ]
The SI unit is (m^{-1}), commonly called the dioptre ((D)).
For example, a converging lens with focal length (0.5m) has power:
[ P=\frac1{0.5}=+2D ]
A diverging lens has negative power under the usual sign convention.
Q29. p-n junction diode
A p-n junction diode is formed by joining p-type and n-type semiconductor materials. A depletion region and a potential barrier form at the junction.
Forward bias: The p-side is connected to the positive terminal and the n-side to the negative terminal of the supply. The potential barrier decreases, allowing substantial current to flow once the applied voltage is sufficient.
Reverse bias: The p-side is connected to the negative terminal and the n-side to the positive terminal. The depletion region widens, and only a small reverse saturation current generally flows until breakdown occurs.
In the current-voltage graph, the forward current increases rapidly after the forward conduction region begins. In reverse bias, the current remains small until the breakdown region is reached.
How to Prepare for the JKBOSE Class 12 Physics Examination
- Revise definitions, laws and formulae from the prescribed textbook.
- Practise electrostatics, current electricity, optics and electromagnetic induction numericals.
- Learn important derivations and their assumptions.
- Practise ray diagrams and circuit diagrams with proper labels.
- Write each numerical solution with the given data, formula, substitution, calculation and final unit.
- Solve available official previous-year papers under timed conditions.
- Review incorrect answers and revise the relevant concepts.
Frequently Asked Questions
1. Is this the actual JKBOSE Class 12 Physics Question Paper 2026?
No. This is an original practice paper. It is not a verified transcription of the actual examination paper.
2. Are answers included?
Yes. The post contains MCQ answers, short-answer solutions and worked numerical problems.
3. How many marks is this practice paper worth?
The illustrative theory paper carries 70 marks. Students must check the official examination scheme for the applicable session.
4. Which chapters should students revise?
Students should revise all units included in their official syllabus, paying particular attention to concepts, derivations, numerical problems and diagrams.
5. Where can I find the original JKBOSE Physics paper?
Check the official JKBOSE website and its examination-related resources. Third-party listings may also identify available sets, but verify the source and paper code before describing a document as official.
6. Can this question paper be downloaded as a PDF?
This page contains the practice paper in web format. A downloadable PDF should be added only after creating the actual PDF file and linking it to the page.
Disclaimer: This educational resource is independently prepared for practice. It is not affiliated with or endorsed by JKBOSE. Confirm the current syllabus, marks distribution and examination pattern using official board documents.