PUNJAB SCHOOL EDUCATION BOARD (PSEB)
CLASS XII – PHYSICS
GUESS QUESTION PAPER
SESSION 2025–26
For Regular & Private Students
Based on Latest Syllabus & Exam Pattern
Important Questions Selected from Multiple Sets
Time Allowed: 3 Hours
PART–A : OBJECTIVE TYPE QUESTIONS (MCQs)
(1 Mark Each)
Choose the correct option:
Capacitance of a conductor depends upon:
(a) Nature of conductor
(b) Size of conductor
(c) Thickness of conductor
(d) NoneKirchhoff’s second law is based on the law of conservation of:
(a) Charge
(b) Momentum
(c) Energy
(d) MassElectrical conductivity of a conductor:
(a) Decreases with increase in temperature
(b) Increases with increase in temperature
(c) Remains constant
(d) Becomes zeroIn an AC circuit containing only a capacitor, the current:
(a) Lags voltage by 90°
(b) Leads voltage by 90°
(c) Is in phase with voltage
(d) Leads voltage by 180°Electromagnetic waves are produced due to:
(a) Charge at rest
(b) Uniformly moving charge
(c) Accelerated charge
(d) Neutral particlesOptical fibres work on the principle of:
(a) Refraction
(b) Reflection
(c) Dispersion
(d) Total internal reflectionWhich of the following waves cannot be polarised?
(a) X-rays
(b) Gamma rays
(c) Radio waves
(d) Sound wavesRed light differs from blue light in:
(a) Speed
(b) Frequency
(c) Amplitude
(d) IntensityThe wavefront produced by a source at infinity is:
(a) Spherical
(b) Cylindrical
(c) Plane
(d) CircularFaraday’s law of electromagnetic induction is related to conservation of:
(a) Charge
(b) Mass
(c) Momentum
(d) EnergyWhen radiation of fixed frequency falls on different metals, the maximum kinetic energy of photoelectrons:
(a) Increases with work function
(b) Decreases with work function
(c) Remains same
(d) Becomes zeroThe radius of an atomic nucleus is of the order of:
(a) 10⁻⁸ m
(b) 10⁻¹⁰ m
(c) 10⁻¹² m
(d) 10⁻¹⁵ mA plane wave passes through a double convex lens. The shape of emerging wavefront is:
(a) Plane
(b) Cylindrical
(c) Spherical
(d) EllipticalLenz’s law is a consequence of conservation of:
(a) Charge
(b) Energy
(c) Mass
(d) MomentumIf distance between two current carrying conductors is doubled, the force between them becomes:
(a) Two times
(b) Four times
(c) Half
(d) One-fourth
True / False
18.In conductors, semiconductors and insulators, the forbidden energy gaps follow the order:
PSEB Guess Papers 2026 – Class 8, 10 & 12 Question Papers |
PB.JOBSOFTODAY.IN
SECTION – B
SHORT ANSWER QUESTIONS
(2 Marks Each)
Q.2. State any two properties of electromagnetic waves.
Q.3. A wire is carrying current. It is charged or not, explain.?
Q.4. Define electric dipole. Write the expression for electric dipole moment.
Q.5. What is wattless current? Why is power factor correction necessary in heavy electrical motors?
Q.6. (A) Define electric flux. State its SI unit.
OR
(B) If 10¹⁹ electrons are removed from a neutral metal plate, calculate the charge left on the plate.
Q.7. (A) Define resistivity of a conductor. Mention any two factors on which it depends.
OR
(B)
Q.8. (A) What is a photon? State any two properties of a photon.
OR
(B) An electron and a proton have the same kinetic energy. Which has greater de-Broglie wavelength? Give reason.
SECTION – C
MEDIUM ANSWER QUESTIONS
(3 Marks Each)
Q.9. Define electric potential. Derive an expression for electric potential due to a point charge. Draw the variation of electric potential with distance.
Q.10. State Kirchhoff’s laws for electric circuits. Explain their significance in solving electrical networks.
Q.11. What is photoelectric effect. Derive Einstein's photo electric equation and explain laws of photo electric effect on the basis of this equation.
Q.12. Using energy band diagrams, distinguish between conductors, semiconductors and insulators.
Q.13. (A) State Ampere’s circuital law. Find the expression for the magnetic field inside a long current-carrying solenoid.
OR
(B) Derive the expression for force per unit length between two long, straight, parallel conductors carrying current.
Q.14. (A) Describe the principle, construction and working of a transformer. Why is the core laminated?
OR
(B) Magnetic flux linked with a coil is given by φ = 5t² − 4t + 1. Find the induced emf at t = 0.2 s.
Q.15. (A) Explain Total intemal reflection of light. What are conditions for it. Define critical angle. Derive relation between refractive Index and critical angle
OR
(B) Two thin lenses of focal lengths +20 cm and −40 cm are placed in contact. Find the focal length of the combination.
SECTION – D
LONG ANSWER & COMPREHENSION TYPE QUESTIONS
(5 Marks Each)
Q.16. Comprehension Type Question
Read the following passage carefully and answer the questions given below:
A current-carrying loop behaves like a magnetic dipole and is characterised by its magnetic dipole moment. When placed in a uniform magnetic field, it experiences a torque. This principle is used in moving coil galvanometers. Magnetic fields due to current-carrying conductors can be calculated using Biot–Savart law and Ampere’s circuital law. A bar magnet can also be treated as an equivalent solenoid. Magnetic substances such as diamagnetic, paramagnetic and ferromagnetic materials show different behaviour in the presence of a magnetic field.
Answer the following questions: (1 × 5 = 5)
(a) What physical quantity defines a current loop as a magnetic dipole?
(b) Which law is used to calculate magnetic field due to a long straight current-carrying conductor?
(c) What effect does a current loop experience in a uniform magnetic field?
(d) Name one device based on the torque acting on a current loop.
(e) Name the type of magnetic substance that is weakly repelled by a magnetic field.
Q.17.
What do you mean by electrical capacitance. Define its unit. Derive a relation for capacitance of a parallel plate capacitor with a dielectric slab between its plates.
OR
Define electric flux. Derive an expression for the electric field due to an infinite uniformly charged plane sheet. What is the value of electric field inside the sheet?
Q.18. (A)
Describe refraction of light through a prism and prove that i + e = $ + A derive prism Formula.
OR
Q.18. (B)
State the necessary conditions for sustained interference of light. Derive the expression for fringe width in Young’s double slit experiment.
