On this page we have uploaded MBOSE HSSLC Class 12 Question Paper for Physics released by www.mbose.in. The question paper provided here from Meghalaya State Board. Download the 2022 question paper pdf as well.
Meghalaya State Board has published subject wise question paper for this year Class 12 students in its official portal www.mbose.in. Here we have published Class 12 MBOSE question paper 2022-23 for Physics subject. For more information regarding Meghalaya HSSLC Class 12 2022 Exam Date, Exam Pattern, Time, Date, How to prepare follow our website.
Meghalaya Board (MBOSE) HSSLC Class 12 Question Papers – Physics Subject
Section – A
Choose the correct option from the following:
(1) For sustained interference of light, we must have
(A) two real monochromatic sources of same wavelength
(B) two real white sources
(C) two virtual sources obtained from a single monochromatic source
(D) two virtual white sources
(2) In terms of susceptibility ϰ, a material is diamagnetic if
(a) ϰ is negative
(b) ϰ is positive and small
(c) ϰ is large and positive
(d) ϰ is zero
(3) The work function of cesium is 2·14 eV. The threshold frequency for cesium is
(a) 8.15 × 1013 Hz
(b) 5.16 × 1014 Hz
(c) 7.12 × 1012 Hz
(d) 9.16 × 1015 Hz
(4) Optical fibres are based on the phenomenon of
(a) reflection
(b) refraction
(c) dispersion
(d) total internal reflection
(5) The magnitude of induced e.m.f. in a coil of inductance 1 mH in which a current is changing from 0·1 A to 2·1 A in 0·01 sec is
(a) 0.02 V
(b) 0.2 V
(c) 2 V
(d) 20 V
Part – II
Answer each of the following questions in 1 sentence/step:
(6) The resistance of a given carbon resistor is 2.4 × 106 Ω ± 5%. What is the sequence of colours on the resistor?
(7) Complete the following nuclear reaction:
(a)
(b)
(8) In passing through a refracting prism, which component colour of white light bends the most? Write the equation for the speed of electromagnetic waves in terms of e0 and µ0.
(9) What is an LED?
(10) Either
Unpolarized light is incident on a plane glass surface of µ = 1.5. What should be the angle of incidence so that the reflected and refracted rays are perpendicular to each other?
Or
Two slits are made 1 mm apart and the screen is placed 1 m away.
What is the fringe separation when light of wavelength 500 nm is used?
Section – B
(Short answer type –I questions)
Answer each of the following questions within 20 to 30 words, wherever applicable:
(11) State Biot-Savart law. Write the equation in vector form.
(12) Either
A uniform magnetic field of 3000 G is established along the positive Z-direction. A rectangular loop of side 10 cm and 5 cm carries a current of 12 A.
What is the torque acting on the loop shown in the figure? (Use 1 G = 10-4 T)
Or
Consider a uniform electric field E = 3 × 103 NC-1, acting along x-axis.
(a) What is the flux through a square of side 10 cm whose plane is parallel to Y-Z plane?
(b) What is the flux through the same square if the normal to its plane makes a 60° angle with the x-axis?
(13) Complete the ray diagram for the incident rays OA, OA1, OA2, OA3.
(14) Either
Define half-life of a radioactive substance. Write the expression for it.
Or
What is mass defect?
Write the expression for the mass defect of a nucleus of mass M, mass number A and atomic number Z.
(15) What are polar and non-polar dielectrics?
(16) Explain briefly the blue colour of the sky on the basis of Rayleigh scattering.
(17) Define the terms magnetic declination and inclination or dip.
(18) How are X-rays generated? What is the wavelength range of X-rays? Mention one use of X-rays.
(19) Either
Draw a properly labelled diagram showing the main components of an AC generator.
Or
What are Eddy currents? How can they be minimised?
Section – C
(Short answer type–II questions)
Answer each of the following questions within 30 to 40 words, wherever applicable:
(20) Either Derive an expression for the mutual inductance of two long co-axial solenoids.
Or
State Lenz’s law. Show that Lenz’s law is a consequence of law of conservation of energy.
(21) Either
What are extrinsic semiconductors? Citing suitable examples, explain how p-type and n-type semiconductors are obtained.
Or
Explain the terms depletion layer and potential barrier for a p-n junction diode.
What happens to the width of the depletion layer when the junction is under forward bias and reverse bias?
(22) Either
With suitable circuit diagram, derive the required expression for the value of shunt, to convert a galvanometer into an ammeter
A galvanometer of resistance 10 Ω gives full-scale deflection for a current of 4 mA. How can it be converted into an ammeter of range 0 to 5 A?
Or
State Ampere’s circuital law.
A part of infinite long wire carrying current I is bent into a circle of radius r as shown in the figure. Calculate the magnetic field at the centre of the circular loop.
(23) Either
Obtain an expression for the torque on a rectangular loop placed in a uniform magnetic field.
Or
Obtain an expression for the magnetic dipole moment of a revolving electron.
(24) Prove that
when refraction takes place for a ray of light travelling from rarer medium to denser medium at a convex spherical refracting surface. (n1 and n2 are the refractive indices of rarer and denser medium)
(25) Either
What is resonance in a series LCR circuit?
Write an expression for the resonant frequency for the same circuit. Also draw a resonance curve in LCR circuit for at least two different values of resistance R.
Or
What is a transformer? Explain the theory and working of a transformer.
(26) Either
What is a rectifier? Explain with circuit diagram the working of a full-wave rectifier.
Or
Explain with circuit diagram, how a Zener diode can function as a voltage regulator.
(27) Deduce the equation for the torque acting on an electric dipole, placed in a uniform electric field.
(28) With regards to the study of photoelectric effect, explain the following terms briefly:
(a) Work function
(b) Cut-off or stopping potential
Also draw a graph showing variation of photoelectric current with collector plate potential for incident radiation of different frequency but same intensity.
Section – D
(Long answer type questions)
Answer each of the following questions within 70 to 80 words, wherever applicable:
(29) Either
State Huygen’s principle for wave theory of light. Using Huygen’s principle, derive the laws of refraction for plane waves.
Or
What are coherent sources? Establish the conditions for constructive and destructive super position of waves emitted by coherent sources.
(30) Either
State Gauss’s law. Using Gauss’s law, derive the equation for the electric field intensity at a point due to an infinitely long straight uniformly charged wire.
Or
Derive the equation for the electric field intensity at a point on the equatorial line of a short electric dipole. Also write the equation in vector form.
(31) Either
State Bohr’s postulates for hydrogen atom.
Using Bohr’s postulate, derive the expression for the energy of an electron in any orbit of the hydrogen atom.
Or
Draw the energy-level diagram for the hydrogen atom. Using equation for the energy of an electron in the nth orbit of hydrogen atom, calculate the energy required to excite an electron from ground state to-
(a) first excited state;
(b) second excited state.
Also find the value of the kinetic energy and potential energy of the electron in the first excited state.