CBSE Class 12 Physics 2024
275 questions · 552 marks · every one with the board’s own marking-scheme answer.
What 2024 actually asked, chapter by chapter
Marks we counted in the 2024 papers themselves. CBSE allocates marks per unit, not per chapter — this is what was observed, not an official CBSE weightage.
| Chapter | Marks | Share |
|---|---|---|
| Current Electricity32 questions | 65 | 11.8% |
| Moving Charges and Magnetism37 questions | 63 | 11.4% |
| Electrostatic Potential and Capacitance22 questions | 63 | 11.4% |
| Ray Optics and Optical Instruments22 questions | 56 | 10.1% |
| Dual Nature of Radiation and Matter27 questions | 43 | 7.8% |
| Alternating Current18 questions | 39 | 7.1% |
| Atoms20 questions | 38 | 6.9% |
| Electromagnetic Induction21 questions | 36 | 6.5% |
| Semiconductor Electronics: Materials, Devices and Simple Circuits16 questions | 34 | 6.2% |
| Electromagnetic Waves19 questions | 34 | 6.2% |
| Wave Optics11 questions | 29 | 5.3% |
| Nuclei11 questions | 26 | 4.7% |
| Electric Charges and Fields13 questions | 18 | 3.3% |
| Magnetism and Matter6 questions | 8 | 1.4% |
All 275 questions from 2024
- Q1The plates P 1 and P 2 of a 2 μ F capacitor are at potentials 25 V and -25 V respectively. The charge on plate P 1 will…1 mk
- Q1Coulomb force F versus (1/(r^2)) graphs for two pairs of point charges ( q 1 and q 2 ) and ( q 2 and q 3 ) are shown in…1 mk
- Q1An isolated conductor, with a cavity, has a net charge +Q. A point charge +q is inside the cavity. The charges on the…1 mk
- Q1Two charges +q each are kept ' 2 a ' distance apart. A third charge -2 q is placed midway between them. The potential…1 mk
- Q1An ammeter and a voltmeter are connected in series to a battery. Their readings are noted as 'A' and 'V' respectively.…1 mk
- Q1A heater coil rated as ( P, V ) is cut into two equal parts. One of the parts is then connected to a battery of V volt.…1 mk
- Q1A battery supplies 0.9 A current through a 2 Ω resistor and 0.3 A current through a 7 Ω resistor when connected one by…1 mk
- Q1The capacitance of a parallel plate capacitor having a medium of dielectric constant K=4 in between the plates is C. If…1 mk
- Q1A thin plastic rod is bent into a circular ring of radius R. It is uniformly charged with charge density λ. The…1 mkasked 3×
- Q1An electric dipole of dipole moment p is kept in a uniform electric field → E. The amount of work done to rotate it…1 mk
- Q1Three point charges, each of charge q are placed on vertices of a triangle ABC, with AB=AC=5 L, BC=6 L. The…1 mk
- Q1Consider a group of charges q 1, q 2, q 3 … such that Σ q ≠ 0. Then equipotentials at a large distance, due to this…1 mk
- Q1Two charged particles P and Q, having the same charge but different masses m P and m Q, start from rest and travel…1 mk
- Q2Three small charged spheres X, Y and Z carrying charges +q,-q and +q respectively are placed equidistant from each…1 mk
- Q2Electrons drift with speed v d in a conductor with potential difference V across its ends. If V is reduced to ((V)/2),…1 mkasked 3×
- Q2The Coulomb force (F) versus (1 / r^2) graphs for two pairs of point charges (q 1. and q 2 ) and ( q 2 and q 3 ) are…1 mk
- Q2A proton is taken from point P 1 to point P 2, both located in an electric field. The potentials at points P 1 and P 2…1 mkasked 3×
- Q2Two identical small conducting balls B 1 and B 2 are given -7 pC and +4 pC charges respectively. They are brought in…1 mk
- Q2Ten capacitors, each of capacitance 1 μ F, are connected in parallel to a source of 100 V. The total energy stored in…1 mk
- Q2A particle of mass m and charge q describes a circular path of radius R in a magnetic field. If its mass and charge…1 mk
- Q2A charged sphere of radius r has surface charge density σ. The electric field on its surface is E. If the radius of the…1 mk
- Q2Two insulated concentric coils, each of radius R, placed at right angles to each other, carry currents I and √3 I…1 mk
- Q2An infinite long straight wire having a charge density λ is kept along y^′ y axis in x -y plane. The Coulomb force on a…1 mk
- Q2An ac voltage is applied across an ideal inductor. The current in it1 mk
- Q3A 2.0 cm segment of wire, carrying 5.0 A current in positive y-direction lies along y -axis, as shown in the figure.…1 mkasked 3×
- Q3The emf induced in a coil rotating in a magnetic field does not depend upon the following:1 mk
- Q3Which of the following pairs is that of paramagnetic materials?1 mk
- Q3A conducting loop is placed in a magnetic field, normal to its plane. The magnitude of the magnetic field varies with…1 mk
- Q3An iron needle is kept near a strong bar magnet. It will experience1 mk
- Q3Which of the following material has its magnetic susceptibility x in the range 0<x<ε, where ε is positive and small?1 mk
- Q3A wire of length 4 · 4 m is bent round in the shape of a circular loop and carries a current of 1.0 A. The magnetic…1 mk
- Q3In a uniform straight wire, conduction electrons move along +x direction. Let E and j be the electric field and current…1 mk
- Q3A student is asked to connect four cells, each of emf E and internal resistance r, in series. But she/he connects one…1 mk
- Q3Consider the circuit shown in the figure. The potential difference between points A and B is:1 mk
- Q3The quantum nature of light explains the observations on photoelectric effect as -1 mkasked 3×
- Q4A piece of wire bent in the form of a circular loop A carries a current I. The wire is then bent into a circular loop B…1 mk
- Q4Two charged particles, P and Q, each having charge q but of masses m 1 and m 2, are accelerated through the same…1 mk
- Q4The radius ( r n ) of n^ th orbit in Bohr model of hydrogen atom varies with n as1 mkasked 3×
- Q4Two thin long parallel wires separated by a distance 'a' carry current ' I ' in opposite directions. The wires will:1 mk
- Q4A loop carrying a current I clockwise is placed in x-y plane, in a uniform magnetic field directed along z -axis. The…1 mk
- Q4Which of the following is a diamagnetic substance?1 mk
- Q4A circular coil of radius 10 cm is placed in a magnetic field B=(1.0 i+0.5 j) mT such that the outward unit vector…1 mkasked 3×
- Q4A circular loop of wire, carrying a current ' I ' is lying in xy -plane with its centre coinciding with the origin. It…1 mk
- Q4A galvanometer of resistance 50 Ω is converted into a voltmeter of range (0-2 V) using a resistor of 1.0 k Ω. If it is…1 mk
- Q4A galvanometer of resistance 100 Ω gives full scale deflection for a current of 1.0 mA. It is converted into an ammeter…1 mk
- Q4A galvanometer shows full scale deflection for a current I g. If a shunt of resistance S 1 is connected to the…1 mk
- Q5A current carrying circular loop of magnetic moment M is suspended in a vertical plane in an external magnetic field B…1 mkasked 3×
- Q5A 10 cm long wire lies along y -axis. It carries a current of 1.0 A in positive y-direction. A magnetic field B=(5 mT)…1 mkasked 3×
- Q5A straight wire is kept horizontally along east-west direction. If a steady current flows in wire from east to west,…1 mk
- Q5Which of the following quantity/quantities remains same in primary and secondary coils of an ideal transformer?…1 mkasked 3×
- Q5The mutual inductance of two coils, in a given orientation is 50 mH. If the current in one of the coils changes as…1 mk
- Q5Two long straight parallel conductors A and B, kept at a distance r, carry current I in opposite directions. A third…1 mk
- Q5Two coils are placed near each other. When the current in one coil is changed at the rate of 5 A / s, an emf of 2 mV is…1 mk
- Q5A particle of mass m and charge q is moving with velocity v=v x i+v y j. If it is subjected to a magnetic field B=B 0…1 mk
- Q5A coil of area of cross-section 0.5 m^2 is placed in a magnetic field acting normally to its plane. The field varies as…1 mk
- Q6A resistor and an ideal inductor are connected in series to a 100 √2 V, 50 Hz ac source. When a voltmeter is connected…1 mk
- Q6The current in a coil of 15 mH increases uniformly from zero to 4 A in 0.004 s. The emf induced in the coil will be:1 mk
- Q6In an ac circuit, the instantaneous values of current (in A) and voltage (in V ) are I=5 sin ω t and E=200 cos (ω…1 mk
- Q6A series LCR circuit ( L=2 mH, C=0 · 2 μ F and R=30 Ω ) is connected to an ac source of variable frequency. The…1 mk
- Q6A coil of N turns is placed in a magnetic field B such that B is perpendicular to the plane of the coil. B changes with…1 mkasked 3×
- Q6A galvanometer of resistance G Ω is converted into an ammeter of range 0 to IA. If the current through the galvanometer…1 mkasked 3×
- Q6The mutual inductance of two coils C 1 and C 2 is 20 mH. In coil C 1, the current changes from 4 A to zero in 0 · 2 s.…1 mk
- Q6The electromagnetic waves used to purify water are1 mkasked 3×
- Q6The average value of the alternating voltage v=(157 V) sin ω t over its first half-cycle is:1 mk
- Q6The magnetic susceptibility for a diamagnetic material is1 mkasked 3×
- Q7Welders wear special glass goggles or face masks with glass windows to protect their eyes from radiations produced by…1 mk
- Q7Consider a solenoid of length l and area of cross-section A with fixed number of turns. The self-inductance of the…1 mkasked 3×
- Q7A conducting circular loop is placed in a uniform magnetic field B=50 mT with its plane perpendicular to the magnetic…1 mk
- Q7Electromagnetic waves with wavelength 10 nm are called:1 mk
- Q7The reactance of a capacitor of capacitance C connected to an ac source of frequency ω is ' X '. If the capacitance of…1 mk
- Q7In four regions I, II, III and IV, the magnetic field is given by: I. B y=B 0 sin kz II. B y=B 0 cos kz III. B y=B 0…1 mk
- Q7The primary and secondary coils of a transformer have 500 turns and 5000 turns respectively. The primary coil is…1 mk
- Q7A galvanometer of resistance 100 Ω is converted into an ammeter of range ( 0-1 A ) using a resistance of 0.1 Ω. The…1 mkasked 3×
- Q7The focal lengths of the objective and the eyepiece of a compound microscope are 1 cm and 2 cm respectively. If the…1 mkasked 3×
- Q8Which one of the following has the highest frequency?1 mk
- Q8A photosensitive surface has a work function of 2 · 00 eV. The maximum kinetic energy of electrons ejected from this…1 mk
- Q8Electromagnetic waves with frequency 1.0 × 10^18 Hz are known as:1 mk
- Q8The variation of the stopping potential ( V 0 ) with the frequency ( v ) of the incident radiation for four metals A,…1 mkasked 2×
- Q8The work function for a photosensitive surface is 3 · 315 eV. The cut-off wavelength for photoemission of electrons…1 mk
- Q8The first scientist who produced and observed electromagnetic waves of wavelengths in the range 25 mm-5 mm was:1 mk
- Q8The momentum (in SI units) associated with a photon of energy 1 · 5 eV is:1 mk
- Q8The electric and magnetic fields of electromagnetic waves are:1 mk
- Q8A plane electromagnetic wave is travelling in air in +x direction. At a particular moment, its electric field E is…1 mk
- Q8In the four regions, I, II, III and IV, the electric fields are described as: Region I: E x=E 0 sin (kz-ω t) Region II:…1 mk
- Q8In a Young's double-slit experiment in air, the fringe width is found to be 0.44 mm. If the entire setup is immersed in…1 mk
- Q8A circular loop A of radius R carries a current I. Another circular loop B of radius r(=(R)/20) is placed…1 mkasked 3×
- Q9The transition of electron that gives rise to the formation of the second spectral line of the Balmer series in the…1 mkasked 3×
- Q9Energy levels A, B and C of an atom correspond to increasing values of energy i.e. E A<E B<E C. Let λ 1, λ 2 and λ 3 be…1 mkasked 3×
- Q9Figure shows the variation of inductive reactance X L of two ideal inductors of inductance L 1 and L 2, with angular…1 mk
- Q9The energy of an electron in the ground state of hydrogen atom is -13.6 eV. The kinetic and potential energy of the…1 mkasked 3×
- Q9The r.m.s. value of a current given by i=(i 1 cos ω t+i 2 sin ω t) is -1 mk
- Q9An ac source V=282 sin (100 t) volt is connected across a 1 μ F capacitor. The rms value of current in the circuit will…1 mk
- Q9A proton and an alpha particle having equal velocities approach a target nucleus. They come momentarily to rest and…1 mkasked 3×
- Q10The figure shows the variation of stopping potential V 0 with frequency v of incident radiation, for three materials M…1 mk
- Q10The variation of the stopping potential ( V 0 ) with the frequency ( v ) of the incident radiation for four metals A,…1 mk
- Q10Ge is doped with As. Due to doping,1 mkasked 3×
- Q10Which one of the following is the correct graph between the maximum kinetic energy ( K m ) of the emitted…1 mk
- Q10A Young's double-slit experimental set up is kept in a medium of refractive index (4/3). Which maximum in this case…1 mk
- Q10The wavelength of matter wave associated with an electron of kinetic energy K is λ. If the kinetic energy of the…1 mk
- Q10An alpha particle approaches a gold nucleus in Geiger-Marsden experiment with kinetic energy K. It momentarily stops at…1 mkasked 3×
- Q10The phase difference between electric field E and magnetic field B in an electromagnetic wave propagating along z -axis…1 mkasked 3×
- Q11An electron makes a transition from n=2 level to n=1 level in the Bohr model of a hydrogen atom. Its period of…1 mkasked 3×
- Q11The potential energy between two nucleons inside a nucleus is minimum at a distance of about1 mkasked 3×
- Q11Two beams, A and B whose photon energies are 3 · 3 eV and 11 · 3 eV respectively, illuminate a metallic surface (work…1 mkasked 3×
- Q11An n-type semiconducting Si is obtained by doping intrinsic Si with:1 mkasked 3×
- Q12A pure Si crystal having 5 × 10^28 atoms m^-3 is dopped with 1 ppm concentration of antimony. If the concentration of…1 mkasked 3×
- Q12When a p-n junction diode is subjected to reverse biasing:1 mkasked 3×
- Q12In Balmer series of hydrogen atom, as the wavelength of spectral lines decreases, they appear1 mkasked 3×
- Q12Si is doped with a pentavalent element. The energy required to set the additional electron free is about:1 mkasked 3×
- Q12A point object is kept 60 cm in front of a spherical convex surface ( n=1.5, radius of curvature 40 cm ). The image…1 mk
- Q12The waves associated with a moving electron and a moving proton have the same wavelength λ. It implies that they have…1 mkasked 3×
- Q13Assertion: Photoelectric current increases with an increase in intensity of incident radiation, for a given frequency…1 mkasked 3×
- Q13Assertion: In a semiconductor, the electrons in the conduction band have lesser energy than those in the valence band.…1 mkasked 3×
- Q13Assertion: In photoelectric effect, the kinetic energy of the emitted photoelectrons increases with increase in the…1 mkasked 3×
- Q13Assertion: Electrons are ejected from the surface of zinc when it is irradiated by yellow light. Reason (R): Energy…1 mkasked 3×
- Q13Assertion: Equal amount of positive and negative charges are distributed uniformly on two halves of a thin circular…1 mkasked 3×
- Q14Assertion: The mutual inductance between two coils is maximum when the coils are wound on each other. Reason (R): The…1 mkasked 3×
- Q14Assertion: Lenz's law is a consequence of the law of conservation of energy. Reason (R): There is no power loss in an…1 mkasked 3×
- Q14Assertion: Photoelectric effect demonstrates the particle nature of light. Reason (R): Photoelectric current is…1 mkasked 3×
- Q14Assertion: The energy of a charged particle moving in a magnetic field does not change. Reason (R): It is because the…1 mkasked 3×
- Q14Assertion: The temperature coefficient of resistance is positive for metals and negative for p -type semiconductors.…1 mkasked 3×
- Q15Assertion: A proton and an electron enter a uniform magnetic field B with the same momentum p such that p is…1 mkasked 3×
- Q15Assertion: In a Young's double-slit experiment, interference pattern is not observed when two coherent sources are…1 mkasked 3×
- Q15Assertion: Two long parallel wires, freely suspended and connected in series to a battery, move apart. Reason (R): Two…1 mkasked 3×
- Q15Assertion: When electrons drift in a conductor, it does not mean that all free electrons in the conductor are moving in…1 mkasked 3×
- Q15Assertion: An electron and a proton enter with the same momentum p in a magnetic field B such that p ⊥ B. Then both…1 mkasked 3×
- Q16Assertion: A convex lens, when immersed in a liquid, disappears. Reason ( R ): The refractive indices of material of…1 mkasked 3×
- Q16Assertion: In interference and diffraction of light, light energy reduces in one region producing a dark fringe. It…1 mkasked 3×
- Q16Assertion: An alpha particle is moving towards a gold nucleus. The impact parameter is maximum for the scattering angle…1 mkasked 3×
- Q16Assertion: The magnifying power of a compound microscope is negative. Reason (R): The final image formed is erect with…1 mkasked 3×
- Q16Assertion: Plane and convex mirrors cannot produce real images under any circumstance. Reason ( R ): A virtual image…1 mkasked 3×
- Q17What is meant by 'relaxation time' of free electrons in a conductor? Show that the resistance of a conductor can be…2 mkasked 3×
- Q17Define resistivity of a conductor. How does the resistivity of a conductor depend upon the following: Number density of…2 mk
- Q17Four point charges of 1 μ C,-2 μ C, 1 μ C and -2 μ C are placed at the corners A, B, C and D respectively, of a square…2 mkasked 3×
- Q17A uniform wire of length L and area of cross-section A has resistance R. The wire is uniformly stretched so that its…2 mk
- Q17An electric field E is maintained in a wire of length ' l ' and area of cross-section 'a'. Derive the relation between…2 mk
- Q17Find the temperature at which the resistance of a wire made of silver will be twice its resistance at 20^° C. Take 20^°…2 mk
- Q17Two batteries of emfs 6 V and 3 V and internal resistances 0 · 8 Ω and 0 · 2 Ω respectively are connected in series to…2 mk
- Q17"The electron drift speed is only a few mm / s for currents in the range of a few amperes for a given conductor." How…2 mk
- Q18The magnifying power of an astronomical telescope is 24. In normal adjustment, distance between its two lenses is 150…2 mkasked 3×
- Q18Monochromatic light of frequency 5.0 × 10^14 Hz passes from air into a medium of refractive index 1 · 5. Find the…2 mkasked 3×
- Q18Two waves, each of amplitude 'a' and frequency ' ω ' emanating from two coherent sources of light superpose at a point.…2 mkasked 3×
- Q18Derive an expression for magnetic force F acting on a straight conductor of length L carrying current I in an external…2 mkasked 3×
- Q18What are matter waves? A proton, an electron and an α -particle have the same kinetic energy. Write the de Broglie…2 mk
- Q18The ratio of de Broglie wavelengths of a proton and a deuteron accelerated by potential V p and V d respectively, ((λ…2 mk
- Q18A proton and α -particle are accelerated through different potentials V 1 and V 2 respectively so that they have the…2 mk
- Q19A convex lens (n = 1.52) has a focal length of 15.0 cm in air. Find its focal length when it is immersed in liquid of…2 mkasked 3×
- Q19A telescope has an objective lens of focal length 150 cm and an eyepiece of focal length 5 cm. Calculate its magnifying…2 mk
- Q19A thin converging lens of focal length 10 cm is placed coaxially in contact with a thin diverging lens of focal length…2 mk
- Q19Explain the following: For a simple microscope, the angular size of the object equals the angular size of the image.…2 mk
- Q19What is a sustained or stable interference pattern? What are the conditions for obtaining such an interference pattern?2 mk
- Q19A ray of light is incident normally on one face of an equilateral glass prism of refractive index μ. When the prism is…2 mkasked 3×
- Q19The radius of curvature of a convex mirror is 30 cm. It forms an image of an object which is half the size of the…2 mk
- Q19Write two points of difference between interference and diffraction of light.2 mk
- Q19An object is placed 30 cm in front of a concave mirror of radius of curvature 40 cm. Find the (i) position of the image…2 mkasked 3×
- Q20Consider a neutron (mass m ) of kinetic energy E and a photon of the same energy. Let λ n and λ p be the de Broglie…2 mkasked 3×
- Q20Deuterium undergoes the following fusion reaction: 1^2 H+ 1^2 H → 2^3 He+ 0^1 n+3.27 MeV How long an electric bulb of…2 mk
- Q20Two electric heaters have power ratings P 1 and P 2, at voltage V. They are connected in series to a dc source of…2 mk
- Q20Calculate the energy released/absorbed in the following nuclear reaction: 6^12 C+ 6^12 C → 10^20 Ne+ 2^4 He Given: m(…2 mkasked 2×
- Q20Two wires A and B of different metals have their lengths in ratio 1: 2 and their radii in ratio 2:1 respectively. I-V…2 mk
- Q20In Bohr model of hydrogen atom, find the ratio of period of revolution of the electron in the orbit n = 2 to that in…2 mk
- Q20Two energy levels of an electron in hydrogen atom are separated by 2.55 eV. Find the wavelength of radiation emitted…2 mk
- Q20The carbon isotope 6^12C has a nuclear mass of 12.000000 u. Calculate the binding energy of its nucleus. Given m p =…2 mk
- Q20Find the temperature at which the resistance of a conductor increases by 25% of its value at 27 °C. The temperature…2 mk
- Q20Light of wavelength 500 nm is incident on caesium metal (work function 2 · 14 eV ) and photoemission of electrons…2 mk
- Q20Calculate the energy released/absorbed (in MeV ) in the nuclear reaction:2 mk
- Q20Light of wavelength 600 nm is incident on potassium (work function 2.3 eV). Will photoemission of electrons occur? What…2 mk
- Q20The minimum intensity of white light that our eyes can perceive is about 0.1 nWm^-2. Calculate the number of photons of…2 mk
- Q21How does the energy gap of an intrinsic semiconductor effectively change when doped with a trivalent impurity, and…2 mkasked 3×
- Q21An air bubble is trapped at point B(CB=20 cm) in a glass sphere of radius 40 cm and refractive index 1.5 as shown in…2 mkasked 3×
- Q21Suppose a pure Si crystal has 5 × 10^28 atoms m^-3. It is doped by 1 ppm concentration of boron. Calculate the…2 mkasked 3×
- Q21How does the conductivity of an intrinsic semiconductor vary with temperature? Explain. Show the variation in a plot.2 mk
- Q21Differentiate between 'diffusion current' and 'drift current'. Explain their role in the formation of p-n junction.2 mk
- Q21Plot a graph showing the variation of current with voltage for the material GaAs. On the graph, mark the region where:…2 mk
- Q21The electron in hydrogen atom is revolving with the speed of 2.2 × 10^6 m / s in an orbit of radius 0.53. Calculate the…2 mk
- Q21The earth revolves around the sun in an orbit of radius 1.5 × 10^11 m with orbital speed 30 km / s. Find the quantum…2 mk
- Q21A proton of energy 1.6 MeV approaches a gold nucleus ( Z=79 ). Find the distance of its closest approach.2 mk
- Q22Determine the current in branches AB, AC and BC of the network shown in figure.3 mk
- Q22The figure shows a circuit with three ideal batteries. Find the magnitude and direction of currents in the branches AG,…2 mkasked 3×
- Q22An air-filled parallel plate capacitor with plate separation 1 mm has a capacitance of 20 pF. It is charged to 4.0 μ C.…3 mk
- Q22A battery of unknown emf E and internal resistance r is connected in a circuit as shown in the figure. When the key ( K…3 mk
- Q22Three point charges Q 1, Q 2 and Q 3 are located in x-y plane at points (-d, 0),(0,0) and (d, 0) respectively. Q 1 and…3 mk
- Q22Write Einstein's photoelectric equation. How did Millikan prove the validity of this equation? Explain the existence of…3 mk
- Q22A current of 1.6 A flows through a wire when a potential difference of 1.0 V is applied across it. The length and…3 mk
- Q22A cube of side 0 · 1 m is placed, as shown in the figure, in a region where electric field E=500 × i exists. Here x is…3 mk
- Q22A photosensitive surface of work function 2.1 eV is irradiated by radiation of wavelength 150 nm. Calculate (i) the…3 mk
- Q22Differentiate between nuclear fission and fusion. The fission properties of 94 Pu^239 are very similar to those of 92…3 mkasked 3×
- Q23A thin spherical conducting shell of radius R has a charge q. A point charge Q is placed at the centre of the shell.…3 mk
- Q23The threshold frequency for a metal is 3.0 × 10^14 Hz. A beam of frequency 9.0 × 10^14 Hz is incident on the metal.…3 mk
- Q23Define the term 'electric flux' and write its dimensions. A plane surface, in shape of a square of side 1 cm is placed…3 mk
- Q23The electric field in a region is given by E=(10 x+4) i where x is in m and E is in N/C. Calculate the amount of work…3 mk
- Q23An electron (charge - e, mass m ) is revolving around a nucleus, in a hydrogen atom, in a circle of radius r. Derive an…3 mk
- Q23On what factors does the speed of an electromagnetic wave in a medium depend? How is an electromagnetic wave produced?…2 mkasked 3×
- Q23Two long straight parallel conductors carrying currents, exert a force on each other. Why? Derive an expression for the…3 mk
- Q23Two conducting spherical shells A and B of radii R and 2 R are kept far apart and charged to the same charge density σ.…3 mk
- Q23A rectangular loop of area A, carrying current I, is placed in a uniform magnetic field B. With the help of a suitable…3 mk
- Q23Define 'current density'. Is it a scalar or a vector? An electric field E is maintained in a metallic conductor. If n…3 mkasked 3×
- Q24Distinguish between reactance and impedance of an ac circuit. Show that an ideal inductor in an ac circuit does not…3 mk
- Q24A 100 -turn coil of radius 1.6 cm and resistance 5.0 Ω is co-axial with a solenoid of 250 turns / cm and radius 1.8 cm.…2 mk
- Q24Draw the graph showing variation of scattered particles detected ( N ) with the scattering angle ( θ ) in…3 mkasked 3×
- Q24A sinusoidal voltage is applied to an electric circuit containing a circuit element ' X ' in which the current leads…3 mk
- Q24Prove that induced charge depends on the net change in the magnetic flux and not on the time interval of the flux…3 mk
- Q24An ac voltage v i=140 sin (100 π t) V is applied to the primary coil having 200 turns, of an ideal transformer and it…2 mk
- Q24A rectangular loop of sides 10 cm × 20 cm is kept outside a region of uniform magnetic field B =5 mT as shown in the…3 mk
- Q24A circular coil with cross-sectional area 0.2 cm^2 carries a current of 4 A. It is kept in a uniform magnetic field of…3 mk
- Q24(i) State Lenz's Law. In a closed circuit, the induced current opposes the change in magnetic flux that produced it as…3 mkasked 3×
- Q24A proton with kinetic energy 1.3384 × 10^-14 J moving horizontally from north to south, enters a uniform magnetic field…3 mk
- Q24(i) Define 'temperature coefficient of resistance' of a metal. (ii) Show the variation of resistivity of copper with…3 mk
- Q24A bar magnet of magnetic moment 2 · 5 JT^-1 lies aligned with the direction of a uniform magnetic field of 0 · 32 T.…3 mk
- Q25In the given network, calculate: (i) effective resistance between points A and M, and (ii) power supplied by the…3 mk
- Q25Two long, straight, parallel conductors carry steady currents in opposite directions. Explain the nature of the force…2 mkasked 3×
- Q25Consider the arrangement of two coils P and Q shown in the figure. When current in coil P is switched on or switched…3 mk
- Q25The electric field in an electromagnetic wave in vacuum is given by: E=(6 · 3 N / C)[ cos (1 · 5 rad / m) y+(4 · 5 ×…3 mkasked 3×
- Q25Draw the graphs showing the variation of the following with the frequency of ac source in a circuit: (i) Resistance…3 mk
- Q25Two long insulated straight wires carrying currents of 3 A and 5 A are arranged in XY plane as shown in figure. Find…3 mk
- Q25Name the part of the electromagnetic spectrum which are (i) stopped by face mask worn by welders. (ii) used in…3 mk
- Q25An electron moving with a velocity v=(1.0 × 10^7 m / s) i+(0.5 × 10^7 m / s) j enters a region of uniform magnetic…3 mkasked 2×
- Q25An inductor, a capacitor and a resistor are connected in series with an ac source v=v m sin ω t. Derive an expression…3 mk
- Q25Find the current in branch BM in the network shown:3 mk
- Q26State Bohr's first and second postulates. Use them to derive an expression for the radius of the n^ th orbit in a…3 mk
- Q26Name the parts of the electromagnetic spectrum which are (i) also known as 'heat waves' and (ii) absorbed by ozone…3 mkasked 2×
- Q26Explain the origin of the spectral lines of hydrogen atom using Bohr's theory. Draw the energy level diagram of…3 mk
- Q26Briefly discuss three characteristics of the forces between nucleons. Which out of 4^8 X and 3^5 Y nuclei is more…2 mk
- Q26What is meant by displacement current? How is this current different from the conduction current? A capacitor is being…3 mk
- Q26A circular loop of radius 10 cm carrying current of 1.0 A lies in x-y plane. A long straight wire lies in the same…3 mk
- Q26Briefly explain de Broglie hypothesis for wave nature of matter. Find the ratio of de Broglie wavelength associated…3 mk
- Q26Using Bohr's postulates, derive the expression for the radius of the n^ th orbit of an electron in a hydrogen atom.…2 mk
- Q26State Bohr's second postulate for his theory of hydrogen atom. Prove that the radius of Bohr's orbit of a hydrogen atom…3 mk
- Q26An infinite straight conductor is kept along X^′ X axis and carries a current I. A charge q at point P(0, r) starts…3 mk
- Q26"The wavelength of the electromagnetic wave is often correlated with the characteristic size of the system that…3 mkasked 3×
- Q27de Broglie wavelength λ as a function of 1√ K, for two particles of masses m 1 and m 2 are shown in the figure. Here, K…2 mk
- Q27Plot a graph depicting potential energy of a pair of nucleons in a nucleus as a function of their separation. Identify…3 mk
- Q27State the three postulates of Bohr's theory of hydrogen atom. A hydrogen atom de-excites from level n to level ( n-1 ).…3 mk
- Q27Name the electromagnetic waves with their wavelength range which are used for (i) FM radio broadcast (ii) detection of…3 mk
- Q27Find the currents flowing through the branches AB and BC in the network shown.3 mk
- Q27Write the drawbacks of Rutherford's atomic model. How did Bohr remove them? Show that different orbits in Bohr's atom…3 mkasked 2×
- Q27Explain the characteristics of a p-n junction diode that makes it suitable for its use as a rectifier. With the help of…3 mkasked 3×
- Q27An electron is moving with a velocity v=(3 × 10^6 ( m)/( s)) i. It enters a region of magnetic field B=(91 mT) k.…3 mk
- Q27Explain the following giving reasons: (i) 'Electromagnetic waves differ considerably in their mode of interaction with…3 mk
- Q27Define atomic mass unit (u). Calculate the energy required to separate a deuteron into its constituent parts (a proton…3 mkasked 3×
- Q27Draw a schematic arrangement of Geiger-Marsden experiment. Briefly explain the conclusions drawn from the observations…2 mk
- Q28Draw the circuit diagrams for obtaining the V-I characteristics of a p-n junction diode. Explain briefly the salient…3 mkasked 2×
- Q28A potential difference of 1.0 V is applied across a conductor of length 5.0 m and area of cross-section 1.0 mm^2. When…3 mk
- Q28Explain the following, giving reasons: A doped semiconductor is electrically neutral. In a p-n junction under…3 mkasked 3×
- Q28(i) Define mutual inductance. Write its SI unit. (ii) Derive an expression for the mutual inductance of a system of two…3 mkasked 3×
- Q28Write two characteristic properties of nuclear force. Draw a plot of potential energy of a pair of nucleons as a…3 mk
- Q28Draw the circuit diagrams for obtaining the V-I characteristics of a p-n junction diode. Explain briefly the salient…3 mk
- Q28State any two properties of a nucleus. Why is the density of a nucleus much more than that of an atom? Show that the…3 mkasked 2×
- Q29The figure shows four pairs of parallel identical conducting plates, separated by the same distance 2.0 cm and arranged…4 mkasked 3×
- Q29When the terminals of a cell are connected to a conductor of resistance R, an electric current flows through the…4 mkasked 3×
- Q29A lens is a transparent medium bounded by two surfaces, with one or both surfaces being spherical. The focal length of…4 mkasked 3×
- Q30Dielectrics play an important role in design of capacitors. The molecules of a dielectric may be polar or non-polar.…4 mkasked 3×
- Q30A lens is a transparent optical medium bounded by two surfaces; at least one of which should be spherical. Applying the…4 mkasked 3×
- Q30A prism is an optical medium bounded by three refracting plane surfaces. A ray of light suffers successive refractions…4 mkasked 3×
- Q30Junction Diode as a Rectifier: The process of conversion of an ac voltage into a dc voltage is called rectification and…4 mkasked 3×
- Q30A pure semiconductor like Ge or Si, when doped with a small amount of suitable impurity, becomes an extrinsic…4 mkasked 3×
- Q30Diffraction and interference are closely related phenomena that occur together. Diffraction is the phenomenon of…4 mkasked 3×
- Q30When a ray of light propagates from a denser medium to a rarer medium, it bends away from the normal. When the incident…4 mkasked 3×
- Q31(i) Derive an expression for potential energy of an electric dipole p in an external uniform electric field E. When is…5 mkasked 3×
- Q31(i) Obtain an expression for the electric potential due to a small dipole of dipole moment p, at a point r from its…5 mkasked 3×
- Q31(i) Draw equipotential surfaces for an electric dipole. (ii) Two point charges q 1 and q 2 are located at r 1 and r 2…5 mkasked 3×
- Q31(i) Obtain the expression for the capacitance of a parallel plate capacitor with a dielectric medium between its…5 mkasked 2×
- Q31(i) Draw a ray diagram for the formation of the image of an object by a convex mirror. Hence, obtain the mirror…5 mkasked 3×
- Q31(i) Give any two differences between the interference pattern obtained in Young's double-slit experiment and a…5 mk
- Q31(i) Obtain the expression for the capacitance of a parallel plate capacitor with a dielectric medium between its…5 mk
- Q32(i) A dielectric slab of dielectric constant ' K ' and thickness ' t ' is inserted between plates of a parallel plate…5 mkasked 3×
- Q32(i) A resistor and a capacitor are connected in series to an ac source v=v m sin ω t. Derive an expression for the…5 mkasked 3×
- Q32(i) (1) What is meant by current sensitivity of a galvanometer? Mention the factors on which it depends. (2) A…5 mkasked 3×
- Q33(i) A particle of mass m and charge q is moving with a velocity v in a magnetic field B as shown in the figure. Show…5 mkasked 3×
- Q33(i) Give any two differences between the interference pattern obtained in Young's double-slit experiment and a…5 mkasked 2×
- Q33(i) Trace the path of a ray of light showing refraction through a triangular prism and hence obtain an expression for…5 mkasked 3×
- Q33(i) A plane light wave propagating from a rarer into a denser medium, is incident at an angle i on the surface…5 mkasked 3×
- Q33(i) A ray of light passes through a triangular prism. Show graphically, how the angle of deviation varies with the…5 mkasked 3×
- Q33(i) You are given three circuit elements X, Y and Z. They are connected one by one across a given ac source. It is…5 mkasked 3×
- Q33(i) Mention the factors on which the resonant frequency of a series LCR circuit depends. Plot a graph showing variation…5 mkasked 3×
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