Maharashtra HSC Class 12 Physics February 2025 question paper with answers

Section A

1 mark each

Q.1 (i)1 mark $"If two systems are each in thermal equilibrium with a third system, they are also in thermal equilibrium with each other." This statement refers to :$
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Q.1 (ii)1 mark $In Bernoulli's theorem, which of the following is constant?$
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Q.1 (iii)1 mark $Which of the following materials belongs to diathermanous substance?$
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Q.1 (iv)1 mark $Electric potential 'V' at a distance 'r' from a point charge is directly proportional to _____.$
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Q.1 (v)1 mark $Which of the following equations gives correct expression for the internal resistance of a cell by using potentiometer?$
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Q.1 (vi)1 mark $\alpha$
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Q.1 (vii)1 mark $The gate which produces high output, when its both inputs are high is -$
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Q.1 (viii)1 mark $2\pi$
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Q.1 (ix)1 mark $A string of length 2 m is vibrating with 2 loops. The distance between its node and adjacent antinode is _____.$
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Q.1 (x)1 mark $A transformer increases an alternating e.m.f. from 220V to 880V. If primary coil has 1000 turns, the number of turns in the secondary coil are _____.$
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Answer the following questions :
Q.2 (i)1 mark $At what temperature the surface tension of a liquid becomes zero?$
Q.2 (ii)1 mark $Define self inductance.$
Q.2 (iii)1 mark $What is the work done by an external uniform magnetic field perpendicular to the velocity of a moving charge?$
Q.2 (iv)1 mark $What do you mean by a thermodynamic system?$
Q.2 (v)1 mark $What is value of B called, when H = 0 is in the hysteresis loop?$
Q.2 (vi)1 mark $State the formula for angle of banking.$
Q.2 (vii)1 mark $\sigma = 8.85\ \mu\text{C/m}^{2}$
Q.2 (viii)1 mark $Find kinetic energy of 1 litre of an ideal gas at S.T.P.$

Section B

2 marks each · attempt any 8

Q.32 marks $Explain harmonics and overtones.$
Q.42 marks $Using Newton's law of viscosity for streamline flow, derive an expression for coefficient of viscosity.$
Q.52 marks $State the formula for magnetic induction produced by a current in a circular arc of a wire. Hence find the magnetic induction at the centre of a current carrying circular loop.$
Q.62 marks $State and prove the law of conservation of angular momentum.$
Q.72 marks $State any four advantages of light emitting diode (LED).$
Q.82 marks $200\ \text{cm}^{2}$
Q.92 marks $Two coils having self inductances 60 mH each, are coupled with each other. If the coefficient of coupling is 0.75, calculate the mutual inductance between them.$
Q.102 marks $3\Omega$
Q.112 marks $State the advantages of a potentiometer over a voltmeter.$
Q.122 marks $Draw a neat and labelled circuit diagram for a full wave rectifier.$
Q.132 marks $A body of mass 0.8 kg performs linear S.H.M. It experiences a restoring force of 0.4N, when its displacement from mean position is 4 cm. Determine Force constant and Period of S.H.M.$
Q.142 marks $A gas of 0.5 mole at 300 K expands isothermally from an initial volume of 2.0 litre to a final volume of 6.0 litre. What is the work done by gas?$

Section C

3 marks each · attempt any 8

Q.153 marks $Obtain an expression for the period of a bar magnet vibrating in a uniform magnetic field, performing S.H.M.$
Q.163 marks $In a thermodynamic system, define - (a) Mechanical equilibrium (b) Chemical equilibrium and (c) Thermal equilibrium$
Q.173 marks $What is Brewster's law? Derive the formula for Brewster's angle.$
Q.183 marks $Derive an expression for law of radioactive decay. Define one becquerel (Bq).$
Q.193 marks $State and prove Kirchhoff's law of heat radiation.$
Q.203 marks $Obtain an expression for practical determination of end correction - (i) for a pipe open at both ends and (ii) for a pipe closed at one end.$
Q.213 marks $A conducting bar is rotating with constant angular speed around a pivot at one end in a uniform magnetic field perpendicular to its plane of rotation. Obtain an expression for the rotational e.m.f. induced between the ends of the bar.$
Q.223 marks $10^{-8}$
Q.233 marks $A flywheel of a motor has mass 100 kg and radius 1.5 m. The motor develops a constant torque of 2000 Nm. The flywheel starts rotating from rest. Calculate the work done during the first 4 revolutions.$
Q.243 marks $50\ \Omega$
Q.253 marks $T = 72$
Q.263 marks $\pi$

Section D

4 marks each · attempt any 3

Q.274 marks $What is Ferromagnetism? Explain it on the basis of domain theory.$
Q.284 marks $Obtain an expression for average power dissipated in a series LCR circuit.$
Q.294 marks $Distinguish between interference and diffraction of light. A double slit arrangement produces interference fringes for sodium light of wavelength 589 nm, that are 0.20 degree apart. What is the angular fringe separation if the entire arrangement is immersed in water? ( R.I. of water = 1.33 )$
Q.304 marks $State Einstein's photoelectric equation and mention physical significance of each term involved in it. The wavelength of incident light is 4000Å. Calculate the energy of incident photon.$
Q.314 marks $2 \times 10^{11}$