CBSE Class 12 Physics 2026
285 questions · 556 marks · every one with the board’s own marking-scheme answer.
What 2026 actually asked, chapter by chapter
Marks we counted in the 2026 papers themselves. CBSE allocates marks per unit, not per chapter — this is what was observed, not an official CBSE weightage.
| Chapter | Marks | Share |
|---|---|---|
| Ray Optics and Optical Instruments37 questions | 86 | 15.5% |
| Electrostatic Potential and Capacitance23 questions | 55 | 9.9% |
| Dual Nature of Radiation and Matter31 questions | 51 | 9.2% |
| Current Electricity25 questions | 48 | 8.6% |
| Moving Charges and Magnetism24 questions | 45 | 8.1% |
| Electromagnetic Induction25 questions | 44 | 7.9% |
| Semiconductor Electronics: Materials, Devices and Simple Circuits22 questions | 44 | 7.9% |
| Nuclei20 questions | 39 | 7.0% |
| Electromagnetic Waves19 questions | 37 | 6.7% |
| Alternating Current14 questions | 34 | 6.1% |
| Wave Optics14 questions | 26 | 4.7% |
| Atoms17 questions | 24 | 4.3% |
| Electric Charges and Fields9 questions | 18 | 3.2% |
| Magnetism and Matter5 questions | 5 | 0.9% |
All 285 questions from 2026
- Q1A particle of mass m and charge q starts from rest and moves in an electric field E=E 0 i. After travelling a distance…1 mk
- Q1A 500 nm photon is incident normally on a perfectly reflecting surface and is reflected. The value of momentum…1 mk
- Q1A wire is gradually stretched to make it 100% longer. Its resistance will increase by:1 mk
- Q1In a region, the electric potential varies as V=10-50 x, where V is in volts and x in meters. The electric field in the…1 mk
- Q1Three point charges 2q, -2q and q are kept at the vertices of an equilateral triangle of side l. The potential energy…1 mk
- Q1In a region electric field is given by E=4 x i N / C. The potential difference between points A(x=1 m) and B(x=3 m),(V…1 mk
- Q1Three point charges +q,-2 q and +q are placed along x -axis at points x=-1 m, x=0 m and x=2 m respectively. The…1 mk
- Q1Two small identical metallic balls having charges q and - 2q are kept far at a separation r. They are brought in…1 mk
- Q1Two wires of same length and same area of cross-section but made of different material of resistivities ρ 1 and ρ 2 are…1 mk
- Q2A square loop of side 50 cm is placed in a uniform magnetic field of 3‧0 T acting perpendicular to the plane of the…1 mk
- Q2A closely wound long solenoid of self-inductance L is cut into two identical solenoids. The value of self-inductance of…1 mk
- Q2Two metal spheres of radii r 1 and r 2( r 1) having charges q 1 and q 2 respectively kept in air, are brought in…1 mkasked 3×
- Q2The momentum of a photon associated with a microwave of wavelength 4 · 00 cm is:1 mk
- Q2The figure represents the variation of the electric potential V at a point in a region of space as a function of its…1 mk
- Q2A conducting wire connects two charged metallic spheres A and B of radii r 1 and r 2 respectively. The distance between…1 mkasked 3×
- Q2Two particles of masses m 1 and m 2 having charges q 1 and q 2 respectively are projected with the same velocity in a…1 mkasked 3×
- Q2A ray of monochromatic light travelling in air is incident on a glass slab and is partly reflected and partly…1 mk
- Q2A photosensitive surface is illuminated by radiations of wavelength λ 1, λ 2 ( λ 1) and λ 3 one by one and…1 mk
- Q3A plane electromagnetic wave travels through a medium and the magnetic field associated with it is given by B=5 × 10^-8…1 mkasked 3×
- Q3Which of the following characteristics of electrons determines the current in the conductor?1 mk
- Q3In Bohr model of hydrogen atom, the value of potential energy of an electron in n^ th orbit varies with ' n ' as1 mk
- Q3A copper wire is stretched to increase its length by 1%. Then the change in its resistance is close to1 mk
- Q3A square loop of side 0.50 m is placed in a uniform magnetic field of 0.4 T perpendicular to the plane of the loop. The…1 mk
- Q3A long straight wire of circular cross-section (radius a) carries a steady current I. The current is uniformly…1 mk
- Q3An electron moves around the nucleus in a circular orbit of radius r and makes n revolutions per second. The value of…1 mk
- Q3An equiconvex lens of focal length 15 cm is cut into two equal plano-convex halves. The focal length of each half will…1 mk
- Q3The maximum kinetic energy of the electrons emitted from a photo sensitive surface depends on1 mk
- Q3Four long straight thin wires are held vertically at the corners A, B, C and D of a square of side 'a', kept on a table…1 mk
- Q4The dimensions of the rate of change of magnetic flux are:1 mk
- Q4An electric dipole P=2 qa i is placed in x-y plane, centred at the origin. Let E 1 and E 2 be the magnitudes of…1 mk
- Q4A thin plano-convex lens and a thin equi-concave lens are kept coaxially in contact as shown in the figure. Assuming…1 mkasked 3×
- Q4In Bohr model of hydrogen atom, for large values of n, the distance between the consecutive orbits is proportional to1 mk
- Q4A square loop of side L lies in the x-y plane in a magnetic field B=B 0(2 i+3 j+4 k), where B 0 is a constant. The…1 mk
- Q4The magnetic flux through a loop placed in a magnetic field can be changed by changing:1 mk
- Q4The shape of the interference fringes in Young's double-slit experiment, when the distance between the slit and the…1 mk
- Q5The electric potential for various points in x -y plane is given by V=1.0 x^2 -2.0 y^2, where V is in volts and x, y…1 mk
- Q5A charged particle is moving in a uniform magnetic field B with a constant speed v in a circular path of radius r.…1 mk
- Q5A concave lens of focal length 40 cm is coaxially in contact with two convex lenses, each of focal length 20 cm, on…1 mk
- Q5A straight long wire lying along y-axis, carries a current of 1 A along -y direction. The magnetic field due to the…1 mk
- Q5A plano-convex lens, made of glass (n=1 · 5) has a curved surface whose radius is 40 cm. The image formed of an object…1 mk
- Q5An electromagnetic wave passes from vacuum into a dielectric medium with relative electrical permittivity (3/2) and…1 mkasked 3×
- Q5In Bohr model of hydrogen atom, an electron makes a transition from n=4 state to n=1 state and a photon of frequency v…1 mk
- Q5An electric dipole with dipole moment P=(2 · 54 × 10^-28 C. m)(2 · 00 i+3 · 00 j) is placed in an electric field…1 mk
- Q5Two identical conductors 1 and 2 are placed on two frictionless conducting rails R and S in a uniform magnetic field…1 mk
- Q5A person is standing facing geographic north and a vertical wire in front of him is carrying a current in downward…1 mk
- Q5Which of the following statements is not true for electric energy in ac form compared to that in dc form?1 mkasked 3×
- Q5The phase difference between the two superimposing waves that give rise to a bright spot in a Young's double-slit…1 mkasked 3×
- Q6The magnetic field in a plane electromagnetic wave travelling in glass (n=1 · 5) is given by B y=(2 × 10^-7 T) sin (α…1 mkasked 3×
- Q6Which of the following materials has positive and small value of magnetic susceptibility?1 mk
- Q6Which one of the following materials has magnetic susceptibility χ in the range -1 ≤ χ<0?1 mk
- Q6An ac voltage is given as v=14 sin (314 t) V. The average and the effective value of the voltage (in V ) over a cycle…1 mkasked 3×
- Q6Figure shows a magnet dropped through a small loop with a small cut. Which of the following statements is correct?1 mk
- Q6The distance-of-closest-approach for an alpha particle is 'd' when it moves head-on with speed v towards a target…1 mk
- Q6In a series LCR circuit, the voltage across the resistor, capacitor and inductor is 10 V each. If the capacitor is…1 mk
- Q6A telescope has an objective lens of focal length 144 cm and an eyepiece of focal length 6.0 cm. The magnifying power…1 mk
- Q6A current of 1.5 A is maintained in a copper wire of length 1 m with area of cross-section 1.7 × 10^-7 m^2. The…1 mk
- Q6Two point charges - Q and Q are located at points (d, 0) and (0, d) respectively, in x-y plane. The electric field E at…1 mk
- Q7The ratio of amplitude of electric field to the amplitude of the magnetic field associated with an electromagnetic wave…1 mkasked 3×
- Q7The expression of magnetic fields associated with four electromagnetic waves are given below: I. B 1=(4 × 10^-6 T) sin…1 mk
- Q7A metallic rod of 1 m length is rotated with a frequency of 40 rev/s, with one end hinged at the centre and the other…1 mk
- Q7Light of which of the following colours will have the maximum energy in a photon associated with it?1 mk
- Q7Electromagnetic waves used for purification of water are1 mk
- Q7Light from a small object in air falls on a spherical glass surface (n=1.5) of radius of curvature R. A real image of…1 mk
- Q7A galvanometer of resistance 27 Ω is converted into an ammeter of range ( 0-10 mA ) using a resistance of 3 Ω. The…1 mkasked 3×
- Q7An electron is moving with velocity v 0 i. If a uniform electric field E=E 0 j is set up in the region, the electron…1 mk
- Q7In which of the following, total internal reflection does not occur?1 mk
- Q7The electric field and the magnetic field components of an electromagnetic wave travelling in vacuum are represented as…1 mk
- Q7If the given figure, V 0 is the potential barrier across a p-n junction in an unbiased condition. Which of the…1 mk
- Q7Electromagnetic waves used in a diagnostic tool in medicine have a wavelength range1 mk
- Q8While studying photoelectric emission from a given surface, the wavelength of the incident radiation is changed from…1 mk
- Q8Radiation of wavelength 200 nm is incident on a photosensitive surface of work function 4 · 2 eV. The kinetic energy of…1 mkasked 2×
- Q8The ratio of the potential energy to the kinetic energy of an electron in n^ th orbit of Bohr model of hydrogen atom is1 mk
- Q8The magnetic flux φ (in Wb ) linked with a coil is related to time t (in s) as φ=5 At^2+Bt-2 C The SI units of A and B…1 mkasked 3×
- Q8Which of the following p-n junction diodes is forward biased?1 mk
- Q8The resistivity ρ of a metal increases with rise in temperature because:1 mk
- Q8A coil having 100 closely wound turns and area of cross-section 300 mm^2 carries a current of 5 mA. The magnitude of…1 mk
- Q8Which of the following substance has relative magnetic permeability μ r 1?1 mk
- Q8Nuclides with the same number of neutrons are called:1 mk
- Q8A charged particle of mass m having kinetic energy K passes undeflected through a region with electric field E and…1 mk
- Q8Two identical circular loops A and B of metal wire are arranged on a table close to each other. Loop A is connected to…1 mk
- Q8The 'distance of closest approach' of an alpha-particle is 'd' when it moves with a velocity v head-on towards the…1 mk
- Q9A rectangular loop of size 5 cm × 8 cm is lying in x-y plane in a uniform magnetic field B=(2 · 0 T) k. The total…1 mk
- Q9A straight conductor lies along x -axis and carries a current of 2 A along +x direction. The magnetic field at a point…1 mk
- Q9A concave lens of focal length 10 cm is cut into two identical plano-concave lenses. The focal length of each lens will…1 mk
- Q9A ray of yellow light undergoes total internal reflection when it is incident at the interface of two media. This ray…1 mk
- Q9Radiation of wavelength 331 nm irradiates the following metals: Which of the following statements is correct?1 mkasked 3×
- Q9The figure shows the variation of capacitive reactance (X C) of two ideal capacitors of capacitances C 1 \& C 2 with…1 mkasked 3×
- Q9The figure shows three point charges kept at the vertices of triangle ABC. The net electric field, due to this system…1 mk
- Q9In Bohr model of hydrogen atom, an electron is moving in an orbit, with total energy -3.4 eV. Its angular momentum will…1 mk
- Q9Two coils are placed closed to each other. The mutual inductance of the pair of coils depends upon the:1 mk
- Q9Welders wear special glass goggles or face masks with glass windows to protect their eyes from1 mk
- Q9A straight conductor lies along x -axis. It carries a current of 10 A along +x direction. The magnetic field B due to 1…1 mk
- Q9A proton and an alpha particle have equal momentum. The ratio of their kinetic energies ( E p / E a ) and de Broglie…1 mk
- Q9The radius of a nucleus of mass number 125 is1 mkasked 3×
- Q10A circular loop has radius R and carries current I as shown in figure. In order that the net magnetic field at the…1 mk
- Q10Which of the following statements is true about mobility of charge carriers in a metal?1 mk
- Q10The angular width of interference fringes in Young's double-slit experiment depends on1 mk
- Q10The kinetic energy of a charged particle is increased to four times of its initial value. The de Broglie wavelength…1 mkasked 3×
- Q10Four independent waves are expressed as (i) y 1=A 1 sin ω t (ii) y 2=A 2 sin 2 ω t (iii) y 3=A 3 cos ω t (iv) y 4=A 4…1 mkasked 3×
- Q10According to Bohr model of hydrogen atom, the time period of an electron in its n^ th orbit is proportional to1 mk
- Q10A magnet held vertically, with its north pole down is dropped along the axis of a closed solenoid placed vertically on…1 mk
- Q10Consider the nuclear reaction X → Y+Z. Let M x, M y and M z be the masses of the three nuclei X, Y and Z respectively.…1 mk
- Q10The energy of an electron in an orbit in hydrogen atom is -3‧4 eV. Its angular momentum in the orbit will be:1 mkasked 3×
- Q10If r 1 and r 2 are the radii of atomic nuclei of mass numbers 64 and 27 respectively, then the value of ((r 1)/(r 2))…1 mkasked 2×
- Q10The ratio of the de Broglie wavelengths associated with the electron revolving in the first and third orbits in…1 mk
- Q11The phenomenon of interference is shown by1 mk
- Q11The equivalent mass of a photon of wavelength 100 nm is1 mk
- Q11A galvanometer of resistance G is converted into a voltmeter of range ( 0-V ) by connecting a resistor of 250 Ω with…1 mk
- Q11The velocity of the photoelectrons emitted from a surface depends upon the: Wavelength of incident radiation only…1 mk
- Q11An electromagnetic wave is propagating along x-axis. At any instant, the phase difference (in radian) between the…1 mk
- Q11When the forward bias voltage in a semiconductor diode is changed from 0.8 V to 1.0 V, the forward current changes by…1 mkasked 3×
- Q11Two points R and S are equidistant from two charges + Q and - 2Q. The work done in moving a charge - Q from point R to…1 mk
- Q11A good diode checked by a multimeter should indicate:1 mkasked 3×
- Q11Two heaters rated as (P 1, V) and (P 2, V) are connected in series across a dc source of (V)/2 volt. The power consumed…1 mk
- Q11Paschen series in spectrum of hydrogen atom lies in:1 mkasked 3×
- Q12In an unbiased p-n junction, at equilibrium, which of the following statements is true?1 mkasked 3×
- Q12A resistor and an inductor of negligible resistance are connected in series to a 20 V ac source. If the voltage across…1 mk
- Q12The energy of an electron revolving in the n^ th orbit in Bohr model of hydrogen atom is proportional to:1 mk
- Q12A point charge of 5 μ C is located at (1 cm, 1 cm) in x -y plane. A second charge of 6 μ C is brought from infinity to…1 mk
- Q12A series LCR circuit with R=3 Ω, X C=4 Ω, X L=8 Ω is connected to a 220 V, 50 Hz ac source. The power factor for the…1 mk
- Q12The rms and the average value of an ac voltage V=V 0 sin ω t volt over a cycle respectively will be:1 mkasked 3×
- Q12In an experiment on photoelectric emission, the intensity of incident radiation is halved keeping its frequency…1 mk
- Q12In a reversed-biased p-n junction diode, the applied voltage mostly drops across:1 mkasked 3×
- Q12Photons of frequency v are incident on the surfaces of two metals A and B of threshold frequencies v/2 and v/3. The…1 mk
- Q12In Bohr model of hydrogen atom, the electron makes a transition from n=5 to n = 1 state. As a result, a photon of…1 mk
- Q12The process named 'minority carrier injection' in a p-n junction diode occurs during:1 mk
- Q13Assertion: Induced emf produced in a coil will be more when the magnetic flux linked with the coil is more. Reason (R):…1 mkasked 3×
- Q13Assertion: The work done, in taking a unit charge around a closed loop of an electric circuit involving cells and…1 mkasked 3×
- Q13Assertion: All atoms have a net magnetic moment. Reason (R): A current loop does not always behave as a magnetic dipole.1 mkasked 3×
- Q13Assertion: On increasing the intensity of incident light of frequency v( v 0) on a photosensitive surface, the…1 mkasked 3×
- Q13Assertion: In a Wheatstone bridge circuit, if we interchange the position of the cell and the galvanometer, the balance…1 mkasked 3×
- Q14Assertion: If accelerated electrons are passed through a narrow slit, a diffraction pattern is observed. Reason (R):…1 mkasked 3×
- Q14Assertion: When a ferromagnetic substance is heated to high temperature it becomes paramagnetic in nature. Reason (R):…1 mkasked 3×
- Q14Assertion: The cylindrical soft iron core in a moving coil galvanometer only makes the magnetic field radial and does…1 mkasked 3×
- Q14Assertion: In Young's double-slit experiment, the fringe width for dark and bright fringes is the same. Reason (R):…1 mkasked 3×
- Q14Assertion: On forward biasing a p-n junction diode, the height of the barrier potential increases. Reason (R): In…1 mkasked 3×
- Q15Reason: The mass of a nucleus is less than the sum of the masses of the constituent nucleons. Reason (R): Energy is…1 mkasked 3×
- Q15Assertion: Light added to light can produce darkness. Reason (R): When two coherent light waves interfere, there is…1 mkasked 3×
- Q15Assertion: Energy is released when heavy nuclei undergo fission or light nuclei undergo fusion. Reason (R): For heavy…1 mkasked 3×
- Q15Assertion: Photoelectric current depends upon the intensity of the incident radiation. Reason (R): Stopping potential…1 mkasked 3×
- Q15Assertion: When a convex lens made of glass is immersed in water, its converging power increases. Reason (R): The focal…1 mkasked 3×
- Q16Assertion: The conductivity of an n -type semiconductor is higher than that of a p-type semiconductor at a given…1 mkasked 3×
- Q16Assertion: Photoelectric effect is a spontaneous phenomenon. Reason (R): According to the wave picture of radiation, an…1 mkasked 3×
- Q16Assertion: Two electric heaters of power P 1 and P 2( P 1) are joined in series across a dc source of voltage V. The…1 mkasked 3×
- Q16Assertion: Nuclear forces are always attractive. Reason (R): The nuclear force between protons and neutrons in a…1 mkasked 3×
- Q16Reason: In Bohr model of hydrogen atom, the energy levels are discrete and quantised. Reason (R): In a hydrogen atom,…1 mkasked 3×
- Q17In a photoelectric experiment, the emitter plate is irradiated with radiation of 200 nm. The photocurrent becomes zero…2 mk
- Q17An electric iron rated 2‧2 kW, 220V is operated at 110 V supply. Find: (i) its resistance, and (ii) heat produced by it…2 mkasked 3×
- Q17In the given figure, a steady current I flows through the circuit when points A and C are connected by a wire of…2 mkasked 3×
- Q17A light copper ring is freely suspended by a light string. A bar magnet is held horizontally with its length along the…2 mk
- Q17An electric dipole consists of two point charges +1 μ C and -1 μ C, held 10 cm apart. It is subjected to a uniform…2 mkasked 3×
- Q17Write two points of difference between intrinsic and extrinsic semiconductors.2 mkasked 4×
- Q17Calculate the de Broglie wavelength of a neutron having kinetic energy of 150 eV.2 mk
- Q18A plane circular coil is rotated about its vertical diameter with a constant angular speed ω in a uniform horizontal…2 mk
- Q18Calculate the temperature at which the resistance of a conductor becomes 20% more than its resistance at 27 °C. The…2 mk
- Q18A ray of light MN is incident normally on the face corresponding with side AB of a prism with an isosceles right-angled…2 mk
- Q18Find ratio (λ a / λ p) of the de Broglie wavelength λ a and λ p associated respectively with an alpha particle and a…2 mkasked 3×
- Q18A beam of light consisting of two wavelengths 400 nm and 600 nm is used to illuminate a single slit of width 1 mm. Find…2 mkasked 3×
- Q18Explain why diffraction of sound is more common in daily experience than that of light.2 mk
- Q18Find the ratio ( λ aλ p) of de Broglie wavelength λ a associated with an alpha particle to de Broglie wavelength λ p…2 mk
- Q18Explain, with the help of suitable diagram, the two important processes that occur during the formation of a p-n…2 mk
- Q18In a Young's double-slit experiment, two waves each of intensity I superpose each other and produce an interference…2 mk
- Q18State Huygens principle. How did Huygens justify the absence of the backwave on a spherical wavefront? OR In a…2 mkasked 3×
- Q19A small bulb is placed at the bottom of a tank, containing a transparent liquid of refractive index √2, to a depth of 1…2 mk
- Q19Explain the terms mass defect and binding energy. How are they related?2 mkasked 3×
- Q19A ray of light is incident on the face of a triangular prism of refracting angle 60° and it just suffers total internal…2 mk
- Q19A wire of length L is bent round into (i) a square coil having N turns and (ii) a circular coil having N turns. The…2 mkasked 3×
- Q19A tank is filled with a liquid to a height of 12 · 5 m. The apparent depth of a needle lying at the bottom of the tank…2 mk
- Q19Light of frequency 5 · 0 × 10^14 Hz is incident on a metal surface. If the maximum speed of photoelectrons emitted is…2 mk
- Q19A ray of light in air is incident at angle ∠i on a face of an equilateral glass prism and is refracted through the…2 mk
- Q19When monochromatic light is incident on a surface separating two media, the refracted and reflected light both have the…2 mk
- Q19A concave mirror of radius of curvature 16 cm produces two-times enlarged real image of an object kept in front of it.…2 mk
- Q20What is the order of magnitude of drift velocity of electrons in a conductor? Deduce the relation between the current…2 mkasked 3×
- Q20A square loop of side 10 cm, free to rotate about a vertical axis coinciding with its one arm, is initially held…2 mk
- Q20A convex lens of refractive index 1.5 has a focal length of 20 cm in air. Find its nature and focal length when it is…2 mk
- Q20Two thin lenses of focal length f 1 and f 2 are placed in contact with each other coaxially. Prove that the focal…2 mk
- Q20A heating element using nichrome is connected to a 220 V supply. Initially it draws a current of 2.9 A. After some…2 mk
- Q20Draw the graph showing the variation of number of scattered alpha particles (N) detected with scattering angle ( θ ) in…2 mk
- Q20Draw a labelled ray diagram of an astronomical telescope when final image is formed at infinity. Write the expression…2 mk
- Q20Why manganin is used in wire-wound standard resistors? Calculate the temperature at which the resistance of a wire…2 mk
- Q20Prove that the density of nuclear matter is same for all nuclei.2 mk
- Q20In an electron microscope, accelerated electrons have wavelength of 0.011 nm. Calculate the voltage through which…2 mk
- Q20A particle of mass M at rest splits up into two particles of masses m 1 and m 2 having non-zero velocities. Calculate…2 mk
- Q21Suppose a nucleus with mass number A=240 and (B. E.)/ =7.6 MeV, breaks into two nuclei, each of mass number A=120 with…2 mk
- Q21A point source, in air, is placed at a distance of 6 cm in front of a convex spherical surface ( n=1 · 5 and radius of…2 mk
- Q21A 5 cm long pencil is placed along the principal axis of a concave mirror of focal length 20 cm such that its nearest…2 mkasked 3×
- Q21Draw a graph showing variation of binding energy per nucleon as a function of mass number A. The binding energy per…2 mk
- Q21How are charge carriers created in an intrinsic semiconductor? Explain.2 mk
- Q21In Young's double slit experiment, the central maximum is bright in the interference pattern obtained on a screen. What…2 mk
- Q21The hole concentration in an intrinsic semiconductor is 5 × 10^8 m^-3. When it is doped with certain impurity, the…2 mkasked 3×
- Q21Suppose a pure Si crystal has 5 × 10^28 atoms per m^3. It is doped with 5 × 10^22 atoms per m^3 of Arsenic. Calculate…2 mkasked 3×
- Q21Draw the plot of potential energy of a pair of nucleons as a function of their separation. Write two important…2 mk
- Q21A ray of light is incident at an angle 2A on one of the faces of a glass prism of refracting angle A. After refraction…2 mk
- Q22Establish the relation between drift velocity of electrons (v d) and electric current (I) in a conductor. How is v d…3 mkasked 2×
- Q22Differentiate between inductive reactance, capacitive reactance and impedance of an ac circuit. An ideal inductor and…3 mk
- Q22What is meant by displacement current? A capacitor is being charged by a battery. Show that Ampere-Maxwell law…3 mk
- Q22State Kirchhoff's rules. Using these rules, find the current flowing through branch FC in the given circuit.3 mk
- Q22Two parallel plate capacitors X and Y are connected in series to a 6 V battery. They have the same plate area and same…3 mkasked 2×
- Q22Consider the following nuclides: 6^12 C, 80^198 Hg, 6^14 C, 79^197 Au Group them into isotopes and isotones. How does…3 mkasked 3×
- Q22Using Gauss's law, deduce an experession for electric field at a point due to a uniformly charged infinite plane thin…3 mkasked 3×
- Q23Calculate the de Broglie wavelength associated with an electron revolving in the second excited state of hydrogen atom.…3 mk
- Q23Figure shows a narrow beam of electrons entering with a velocity of 3 × 10^7 m / s, symmetrically through the space…3 mkasked 3×
- Q23A ray of light is incident at angle of 45° on one face of a prism with an equilateral triangular base. If it passes…3 mk
- Q23A circular coil of 30 turns and radius 8.0 cm carrying a current of 6 A is suspended vertically in a uniform horizontal…3 mkasked 3×
- Q23Define the term 'critical angle'. A small bulb is placed at the bottom of a tank containing a liquid of refractive…3 mk
- Q23A parallel plate capacitor of capacitance C has a dielectric slab between its plates. It is charged to a potential…3 mk
- Q23Write the expression for the magnetic field due to a current element in vector form. Consider a 1 cm segment of a wire,…3 mkasked 3×
- Q23An electric field E=E 0 i exists in a region of space. Draw three equipotential surfaces in the region. Two point…3 mk
- Q23The figure given below shows three straight long parallel conductors (1), (2) and (3) kept in x-y plane, carrying…3 mkasked 3×
- Q23Can a transformer step up or step down dc power supply? Can a step up transformer work as a step down transformer? Does…3 mk
- Q24Name the electromagnetic waves which are used for (i) detection of fractures in bones (ii) physiotherapy (iii) radar…3 mk
- Q24Discuss the behaviour of an inductor connected to (i) a dc source, and (ii) a high frequency ac source. What is the…3 mk
- Q24The figure given below shows a square-shaped loop MNOP of side 25 cm placed horizontally in a uniform magnetic field B…3 mk
- Q24A long solenoid of length L and radius r 1 having N 1 turns is surrounded symmetrically by a coil of radius r 2( r 1)…3 mk
- Q24In Bohr model of hydrogen atom, calculate: the radius of the innermost electron orbit, and the speed of electron in…3 mk
- Q24Name the electromagnetic waves which are used 3 (i) as a diagnostic tool in medicine (ii) in remote switches for TV…3 mk
- Q25What are infrared waves? Why are these waves referred to as 'heat waves'? Give any two uses of these waves.3 mk
- Q25A series combination of circuit elements X and Y is connected across an ac source. It is found that the voltage is…3 mk
- Q25(i) Draw electric field lines and equipotential surfaces for a system of two equal and opposite point charges separated…3 mk
- Q25Depict the variation of electric field ( E) and magnetic field ( B) with respect to the direction of propagation of an…3 mkasked 3×
- Q25Two point charges q 1=2 · 5 × 10^-7 C and q 2=-2 · 5 × 10^-7 C are located at points (0, 0, - 15 cm) and (0, 0, 15 cm)…3 mk
- Q25What is displacement current (i d)? Considering the case of charging of a capacitor, show that i d=ε 0 d φ Edt. What is…3 mk
- Q25What are X-rays? How are they produced? Give two uses of X-rays.3 mk
- Q25(i) Define mutual inductance of a pair of coils. Write its SI unit. (ii) A long solenoid of radius R and length L has n…3 mkasked 3×
- Q25An ac voltage V i=12 sin (100 π t) V is applied between points A and B in a network of two ideal diodes and three…3 mkasked 3×
- Q26What are microwaves? How are they produced? Give any two uses of microwaves.3 mk
- Q26(i) Write any two features of nuclear forces. (ii) If both the number of protons and the neutrons are conserved in each…3 mkasked 3×
- Q26A 12.0 μ F capacitor is charged to a potential difference of 150 V. The terminals of the charged capacitor are then…3 mk
- Q26Distinguish between isotopes and isobars, giving one example for each. Derive the relation between atomic mass unit (u)…3 mk
- Q26A parallel plate capacitor of capacitance C is charged to V volt by a battery. After sometime the battery is…3 mk
- Q26A ray of light is travelling through a rectangular glass slab (refractive index 3/2 ) and is incident on the horizontal…3 mk
- Q26Briefly explain the two important processes that occur during the formation of a p-n junction.3 mk
- Q26Draw electric field lines and equipotential surfaces for a system of two equal positive charges separated by some…3 mk
- Q26Explain how the dual aspect of matter is evident in the de Broglie relation. Radiation of wavelength λ is incident on a…3 mkasked 3×
- Q26State Bohr's second postulate and mention its significance. Prove that, in Bohr model of hydrogen atom as principal…3 mk
- Q27'Current is a scalar quantity, although we represent current with an arrow.' Explain. Derive the balance condition of a…3 mk
- Q27Differentiate between conduction current and displacement current. A capacitor is connected across a source providing…3 mk
- Q27Differentiate between nuclear fission and nuclear fusion. Give one example for each with nuclear reaction.3 mkasked 3×
- Q27A semiconductor has equal electron and hole concentration of 3 × 10^8 m^-3. On doping with a certain impurity, the hole…3 mk
- Q27A conducting rectangular loop of area 5 cm^2 and resistance 4 Ω is removed from a region of uniform magnetic field,…3 mk
- Q27Draw the ray diagram to show the image formation by a refracting telescope and write the expression for angular…3 mk
- Q27Photoemission of electrons occurs from a metal ( φ 0=1 · 96 eV ) when light of frequency 6.4 × 10^14 Hz is incident on…3 mkasked 3×
- Q27In the nuclear reaction: 1^2 H+ 1^2 H → 2^A X+ 0^1 n Find the value of A. Calculate the amount of energy released in…3 mk
- Q27Name the electromagnetic waves which are (i) also known as 'heat waves', (ii) used in LASIK eye surgery, (iii) used to…3 mk
- Q27State Faraday's law of electromagnetic induction. Briefly describe two methods for producing induced emf.3 mk
- Q27Draw the V-I characteristics of silicon diode. Explain the following terms: (i) minority carrier injection in forward…3 mk
- Q28Derive an expression for the magnetic field B, due to a circular coil of N turns, each of radius r carrying current I,…3 mkasked 3×
- Q28With the help of circuit diagrams, briefly explain the forward biasing and the reverse biasing of a p-n junction diode.3 mkasked 3×
- Q28A particle of charge q and mass m is accelerated through a potential difference V. Deduce an expression for the de…3 mk
- Q28Explain the statement: "Current is a scalar although we represent current with an arrow". Use Kirchhoff's rules to find…3 mkasked 3×
- Q28Draw a plot showing the variation of potential energy of a pair of nucleons as a function of their separation (r).…3 mk
- Q28Draw a circuit diagram of a full-wave rectifier using p-n junction diodes. Explain its working and show the…3 mkasked 2×
- Q28Why does one prefer to view the image formed at infinity than that formed at near point in microscope/telescope?…3 mk
- Q28State the two conditions under which total internal reflection occurs. A transparent container contains layers of three…3 mkasked 3×
- Q28The two Kirchhoff's rules are based on law of conservation of two physical quantities. Name the quantities. Find…3 mk
- Q28With the help of a circuit diagram, explain the working of a full wave rectifier. Depict the input and output waveforms.3 mkasked 3×
- Q28Draw a labelled ray diagram showing the formation of image by a compound microscope when final image is formed at least…3 mk
- Q28Two coils, one of radius 0.5 cm having 10 turns and the other of radius 5 cm having 50 turns are placed coaxially in…3 mk
- Q28What are de Broglie waves? Show that the wavelength of the electromagnetic radiation is equal to the de Broglie…3 mk
- Q28A deuterium nucleus and an alpha particle approach a target nucleus separately in head-on position. Find the ratio of…3 mk
- Q29A galvanometer is used to detect or/and measure small currents in an electrical circuit. It essentially works on the…4 mkasked 3×
- Q29The electric potential (V) and electric field (E) are closely related concepts in electrostatics. The electric field is…4 mkasked 3×
- Q29Capacitors are manufactured with certain standard capacitances and working voltages. However, these standard values may…4 mkasked 3×
- Q29A p-type or n-type semiconductor can be converted into a p-n junction by doping it with suitable impurity. The motion…4 mkasked 3×
- Q30A student sets up the circuit as shown in the figure to find the value of unknown resistance X and records a set of…4 mkasked 3×
- Q30In a Young's double-slit experiment, the two slits behave as coherent sources. When coherent light waves superpose over…4 mkasked 3×
- Q30A researcher performs an experiment on photo-electric effect using two metals A and B with unknown work functions. She…4 mkasked 3×
- Q30An astronomical telescope consists of two converging lenses. One of them of large aperture and large focal length is…4 mkasked 3×
- Q30In an experiment with convex lens of focal length f, the screen is fixed at a distance D from the object. A student…4 mkasked 3×
- Q30A charged particle +q in an electric field E experiences a force in the direction of the electric field. As a result,…4 mkasked 3×
- Q31(i) In the figure, OA and OB show the variation of electric potential V at a point due to two point charges Q 1 and Q 2…5 mkasked 3×
- Q31An electric dipole consists of two point charges q and -q separated by a distance 2a. Derive an expression for the…5 mkasked 3×
- Q31What are coherent sources? Why they are necessary for observing stable interference pattern? Draw a graph showing the…5 mkasked 3×
- Q31(i) Derive the condition for which a Wheatstone Bridge is balanced. (ii) Determine the current in 3 Ω branch of a…5 mkasked 3×
- Q32Derive an expression for the capacitance of a parallel plate capacitor of plate area A and plate separation d with air…5 mkasked 3×
- Q32(i) A rectangular loop of sides a and b carrying current I is placed in a magnetic field B such that its area vector A…5 mkasked 3×
- Q32(i) A light bulb and an open coil inductor are connected in series across an ac source of variable frequency. How will…5 mkasked 3×
- Q32(i) Define the terms (I) resonant frequency, and (II) power factor of a series LCR circuit. For what value of the power…5 mkasked 3×
- Q32(i) Define refractive index of a medium in terms of speed of light. (ii) Derive the relation for the refractive index (…5 mkasked 3×
- Q32Using the relation for refraction at a curved spherical surface, derive the expression for lens maker's formula. Three…5 mkasked 3×
- Q33(i) Explain the following statements giving reason: (I) An equipotential surface through a point is normal to the…5 mkasked 3×
- Q33(i) A point object is kept in front of a convex spherical surface of radius of curvature R. Draw the ray diagram to…5 mkasked 3×
- Q33(i) A parallel beam of monochromatic light falls normally on a single slit of width 'a' and a diffraction pattern is…5 mkasked 3×
- Q33A series combination of L, C and R is connected to an a.c. source. Using a phasor diagram, derive an expression for the…5 mkasked 3×
- Q33State Faraday's law of electromagnetic induction. Derive an expression for the self-inductance of an air-filled long…5 mkasked 3×
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