TN 12th Standard Physics Quarterly Exam Question Paper (Sept 2025) - Tenkasi District
Introduction
Welcome to our educational portal! If you are preparing for your Tamil Nadu State Board exams and looking for the latest Class 12 Physics question papers, you are in the right place.
Below are the complete details and the download link for the Tenkasi District Common Quarterly Examination - September 2025 for Standard 12 Physics
Exam Overview
Subject: Physics
Standard: 12th
Medium: English
District: Tenkasi
Month/Year: September 2025
Maximum Marks: 70
Time Allowed: 3.00 Hours
Question Paper Structure
The question paper follows the standard board pattern and is divided into four main sections
Part-I: Contains 15 multiple-choice questions for 1 mark each (15 marks total)
. Part-II: Requires answering any six 2-mark questions out of nine, with Question No. 24 being a compulsory problem (12 marks total)
. Part-III: Requires answering any six 3-mark questions, with Question No. 33 being a compulsory problem (18 marks total)
. Part-IV: Contains five 5-mark questions with internal "OR" choices, demanding detailed descriptive answers (25 marks total)
.
Key Topics Covered in this Exam
For students analyzing the paper for important topics, this quarterly exam heavily features
Electrostatics & Current Electricity: Key questions cover the electrostatic potential due to a dipole, microscopic form of Ohm's law, and determining internal resistance using a voltmeter
. Magnetism: Includes evaluating the properties of magnetic dipoles with specific vector moments, the working principle of a cyclotron, and comparing dia, para, and ferro magnetism
. Electromagnetism & AC Circuits: Features questions on Lenz's law, step-up/step-down transformers, and the working of a single-phase AC generator
. Optics: Covers the derivation of the mirror equation and optical path calculations for light traveling through a glass slab
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The Original Question Paper
PART - I
Choose the best answer: (15 × 1 = 15)
If 20J of work is done in bringing a negative charge towards a positive charge, then the electrostatic potential energy will be
a) 20J b) -20J c) 10J d) -10J A parallel plate capacitor stores a charge 'Q' at a voltage 'V'. Suppose the area of the parallel plate capacitor and the distance between the plates are each doubled then which is the quantity that will change?
a) Capacitance b) Charge c) Voltage d) Energy density In India electricity is supplied for domestic use at 220V. It is supplied at 110V in USA. If the resistance of a 60W bulb for use in India is R, the resistance of a 60W bulb for use in USA will be
a) R b) 2R c) R/4 d) R/2 A piece of copper and another of germanium are cooled from room temperature to 80K. The resistance of
a) each of them increases b) each of them decreases c) copper increases and germanium decreases d) copper decreases and germanium increases The value of Bohr magneton which is used to measure atomic magnetic moments is
a) 9.27 x 10^24 Am² b) 9.27 x 10^-24 Am² c) 8.78 x 10^10 Am² d) 8.78 x 10^-10 Am² The potential energy of magnetic dipole whose dipole moment is Pm = (0.5i + 0.4j) Am², kept in an uniform magnetic field B = 0.2i T
a) -0.1J b) -0.8J c) 0.1J d) 0.8J Power delivered by Lorentz force on the particle of charge q moving with velocity V is
a) Zero b) F.V c) qV²B sinθ d) infinity A step-down transformer reduces the supply voltage from 220V to 11V and increase the current from 6A to 100A. Then its efficiency is
a) 1.2 b) 0.83 c) 0.12 d) 0.9 In a series RL circuit, the resistance and inductive reactance are same. Then the phase difference between the voltage and current in the circuit is
a) π/4 b) π/2 c) π/6 d) Zero The truth of Lenz's law can be established on the basis of the
a) Law of conservation of momentum b) Law of conservation of angular momentum c) Law of conservation of energy d) Law of conservation of isospin Which of the following is an electromagnetic wave?
a) α rays (alpha) b) β rays (beta) c) γ rays (gamma) d) All of them Fraunhofer lines are an example of
a) line emission b) line absorption c) band emission d) band absorption spectrum If the amplitude of the magnetic field is 3 x 10^-6 T, then amplitude of the electric field for a electromagnetic waves is
a) 100 V/m b) 300 V/m c) 600 V/m d) 900 V/m Stars twinkle due to
a) reflection b) total internal reflection c) refraction d) polarization For the light incident from air on a slab of refractive index 2, the maximum possible angle of refraction is
a) 30° b) 45° c) 60° d) 90°
PART - II
i) Answer any six questions. ii) Question No. 24 is compulsory. (6 × 2 = 12)
The electric field lines never intersect. Justify.
State Joule's law of heating.
Define current density.
Compute the magnitude of the magnetic field of a long straight wire carrying a current of 1A at a distance of 1m from it.
What is meant by hysteresis?
Write any two differences between stepup transformer and step down transformer.
What are electromagnetic waves?
Why does sky appear blue?
A straight conducting wire is dropped horizontally from a certain height with its length along east-west direction. Will an emf be induced in it? Justify your answer.
PART - III
i) Answer any six questions. ii) Question No. 33 is compulsory. (6 × 3 = 18)
Obtain Gauss law from Coulomb's law.
State and explain Kirchhoff's rules.
Discuss the conversion of galvanometer into voltmeter.
Compare dia, para, ferro magnetism.
How will you induce an emf by changing the area enclosed by the coil?
Mention the various energy losses in a transformer.
Write any six properties of electromagnetic waves.
Derive the relation between f and R for a spherical mirror.
Light travels from air into a glass slab of thickness 50 cm and refractive index 1.
5. a) What is the speed of light in the glass slab? b) What is the time taken by the light to travel through the glass slab? c) What is the optical path of the glass slab?
PART - IV
Answer all the questions: (5 × 5 = 25)
a) Derive the expression for resultant capacitance, when capacitors are connected in series and parallel.
(OR) b) Derive an expression for electrostatic potential due to an electric dipole. a) Describe the microscopic model of current and obtain microscopic form of ohm's law.
(OR) b) Explain the determination of internal resistance of a cell using voltmeter. a) Derive the expression for the force between two parallel current carrying conductors.
(OR) b) Discuss principle, construction and working of cyclotron in detail. a) Show that the mutual inductance between a pair of coils is same. (M12 = M21)
(OR) b) Explain the working of a single phase AC generator with necessary diagram. a) Write down Maxwell equations in integral form, and explain them.
(OR) b) Derive the mirror equation.