II PUC Physics Past Paper PDF

# ELECTRIC CHARGES AND FIELDS ## MULTIPLE CHOICE QUESTIONS 1. When a glass rod is rubbed with silk cloth, * silk cloth will lose electrons to glass rod * glass rod will lose electrons to the silk cloth * glass rod acquires negative charge * silk acquires positive charge 2...

# ELECTRIC CHARGES AND FIELDS ## MULTIPLE CHOICE QUESTIONS 1. When a glass rod is rubbed with silk cloth, * silk cloth will lose electrons to glass rod * glass rod will lose electrons to the silk cloth * glass rod acquires negative charge * silk acquires positive charge 2. The electric field at a distance 'r' from infinitely long straight uniformly charged wire is * inversely proportional to r * inversely proportional to cube of r * inversely proportional to square of r * independent of r 3. Which one of the following charges is NOT possible? * 1.602 × 10^-19 C * 3.204 x 10^-19 C * 5.607 × 10^-19 C * 6.408 × 10^-19 C 4. F= k *q₁*q₂ / r² where k is * 9 x 10⁹ Nm²/ C² * 9 x 10⁹ NC²/ m² * 9 x 10^-9 Nm²/ c² * 9 x 10⁹N 5. The electrostatic force between the two charges in vacuum is given by * 9 x 10⁹ Nm²/ C² 6. The force on any charge due to a number of other charges is the vector sum of all the forces on that charge due to the other charges. This statement is called * quantization principle of charges * principle of superposition of electric forces * principle of homogeneity * additivity of charges 7. The direction of electric field vector at a point on the equatorial line of a dipole is * in the same direction of dipole moment * in the opposite direction to the dipole moment * towards negative charge * towards positive charge 8. Dipole moment is a vector quantity, which is pointing from * -q to +q along the axis of an electric dipole. * +q to -q along the axis of an electric dipole. * infinity to +q * +q to infinity. 9. Name the physical quantity which has the dimensional formula [LTA] * line charge density * capacitance * dipole moment * charge 10. placed in an electric field experiences a force in the direction opposite to the electric field. * An electron * A positive charge * A neutron * A proton. 11. When a free electric dipole placed in a non-uniform electric field, the dipole will experience * both force and torque * only force but not torque * only torque but not force * neither torque nor force 12. Electrostatic field lines can never form closed loops. This is due to * Conservation of charges. * Conservation of momentum. * Quantization of electric charges * Conservative nature of electrostatic field 13. SI unit of electric flux is * NC * Weber * NC * Nm²C 14. Electric field intensity at a distance r from center of uniformly charged sphere outside the sphere is E. Which one of the following is correct? * E α q and E α 1/r² * E α 1/r² and E α 1/r * E α q and E α 1/r * E α 1/r and E α 1/r² 15. The electric field due to an electric dipole at any point on its axis, which is at distance r (r >> length of dipole) from its center varies according to * E α 1/r * E α 1/r² * E α 1/r³ * E α 1/r⁴ ## FILL IN THE BLANKS * The electric field lines due to a single positive charge end at **infinity**. * The electric field inside a uniformly charged spherical shell is **zero**. # ELECTROSTATIC POTENTIAL AND CAPACITANCE ## MULTIPLE CHOICE QUESTIONS: 1. Name the physical quantity whose SI unit is joule per coulomb. * Power * electric field * electric potential * dipole moment 2. **eV** is a unit of energy. * V * Vm * Vm^-1 * eV 3. Equal charges are given to the two spheres of different radii. The potential will: * Be more on bigger sphere * Be more on smaller sphere * Be equal on both the spheres * Depend on the nature of the materials of the spheres 4. For linear dielectrics, the ratio of dielectric polarisation to the applied electric field is equal to * Mobility * Dipole moment * ε × Susceptibility * Permittivity 5. The dimension of electric polarisation is given by * [L^-1AT] * [LAT] * [ML^-1A^-1T^-3] * [M^-1L^-2A²T^-1] 6. The electric potential at the surface of a charged spherical shell of radius 10 cm is 20 V. The electric potential at the center of the shell is * Zero * 10 V * 20 V * 30 V 7. The electric field at a point which is very close to the surface of a charged conductor with surface charge density σ is * E = σ / ε₀ * E = σ / 2ε₀ * E = 2σ / ε₀ * E = σ / ε₀ 8. The energy density between the plates of a charged capacitor is given by * CV² * ε₀ E² * ε₀ E² / 2 * QV 9. The potential energy of an electric dipole placed in a uniform electric field is * -p.Ε * -p × E * CV² * σ / ε₀ * E² 10. An electric dipole is placed in a uniform electric field. The dipole moment makes an angle θ with the electric field. For what angle θ is the potential energy of the dipole maximum? * θ = 0° * θ = 45° * θ = 90° * θ = 180° 11. Capacitance of a capacitor is defined as C = q/V. A factor on which capacitance of the capacitor depends is: * Charge q * Potential deference V * Geometry of the conductor * all of the above 12. Capacity of a parallel plate capacitor can be increased by * increasing the distance between the plates * increasing the thickness of the plates * decreasing the area of the plates * decreasing the distance between the plates 13. The potential energy of a capacitor is stored in the **electric field** between the plates of the capacitor. * electric charges * electric field * magnetic field * current 14. Which of the following correctly describes the behavior of polar and nonpolar dielectrics in an electric field? * Both polar and nonpolar dielectrics have permanent dipole moments, but only nonpolar dielectrics align in an external field. * Polar dielectrics align their dipole moments with the external field, while in the case of nonpolar dielectrics a dipole moment is induced in response to the field. * Nonpolar dielectrics align their permanent dipole moments in an external field, while polar dielectrics remain unaffected. * Polaectrics and nonpolar dielectrics behave identically in the presence of an electric field, showing no difference in polarization. 15. An electric dipole is placed inside an insulating spherical shell. Pick the wrong statement. * Net charge enclosed by the shell is zero * Sphere acts as equipotential surface. * Electric flux through the sphere is zero. * Electric field is not uniform across the surface of the spherical shell. 16. The following graphs show the variations of two physical quantities with distance 'r' from the center of a uniformly charged spherical shell. Identify the graphs. * First graph shows variation of E versus r and second is V versus r * First graph shows variation of V versus r and second is E versus r * Both graphs shows the variation of V versus r * Both graphs shows the variation of E versus r 17. Statement 1: The electric field inside a conductor is zero. * Both statements are correct and Statement 2 is the correct explanation for the Statement 1. * Both statements are correct and Statement 2 is not correct explanation for the Statement 1. * Statements 1 is correct and Statement 2 is wrong * Statements 1 is wrong and Statement 2 is correct 18. An imaginary sphere radius R is drawn around a charge Q, keeping the charge Q at its center. The work required to move a test charge q from point A to point B is * q(2R) * qVA * zero * qVB 19. Consider the following statements: * Both statements are correct and Statement 2 is the correct explanation for the Statement 1. * Both statements are correct and Statement 2 is not the correct explanation for the Statement 1. * Statements 1 is correct and Statement 2 is wrong * Statements 1 is wrong and Statement 2 is correct 20. The equivalent capacitance of the combination is * ½ * (C₁ + C₂) * (C₁*C₂)/ (C₁ + C₂ * (C₁ + C₂ + C)/ (C₁*C₂) * (C₁*C₂)/ (C₁ + C₂ + C) ## FILL IN THE BLANKS: * The electric potential at the surface of a charged spherical shell is **constant**. * **Electric dipole** is the potential energy of an electric dipole, when dipole moment p is perpendicular to electric field E is. # CURRENT ELECTRICITY ## MULTIPLE CHOICE QUESTIONS: 1. The SI unit of current is * coulomb * ampere * newton * farad 2. When no current is passed through a conductor, * the free electrons do not move * the average speed of a free electron over a large period of time is not zero * the average velocity of a free electron over a large period of time is zero * the average of the velocities of all the free electrons at an instant is non zero 3. In the absence of an electric field, the mean velocity of free electrons in a conductor at absolute temperature (T) is * Zero * independent of T * proportional to T * proportional to T² 4. Ohm's law is valid when the temperature of conductor is * very low * very high * constant * varying 5. In the equation J * B = C, J is the current density, C is the electric field, Then B is * resistivity * conductivity * resistance * potential difference 6. Which of the following is non-ohmic resistance? * Lamp filament * Copper wire * Carbon resistor * Diode 7. The relaxation time in conductors * increases with the increase of temperature * decreases with the increase of temperature * it does not depend on temperature * all of sudden changes at 400 K 8. With increase in temperature the conductivity of * semiconductors increases and metals decreases. * metals increases and of semiconductor decreases. * in both metals and semiconductors increases. * in both metal and semiconductor decreases. 9. Drift velocity of electrons is due to * motion of conduction electrons due to random collisions. * motion of conduction electrons due to electric field E * repulsion to the conduction electrons due to inner electrons of ions. * collision of conduction electrons with each other. 10. Constantan wire is used for making standard resistance, because it has * high melting point * low specific resistance * high specific resistance * negligible temperature coefficient of resistance 11. The resistivity of a wire * increases with the length of the wire * decreases with the area of cross-section * decreases with the length and increases with the cross-section of wire * none of the above statement is correct 12. n identical cells of each emf E and internal resistance r are connected in series. An external resistance R is connected in series with this combination. The current through R is * RE / (R + nr) * RE / (R + r) * E / (R + nr) * nE / (R + r) 13. If the terminals of a cell are connected to an external resistance then the potential difference across its terminals is * more than emf of the cell * less than emf of the cell * equal to emf of the cell * equal to potential drop across its internal resistance 14. Kirchhoff's first law, i.e., ΣI = 0 at a junction, deals with the conservation of * Energy * Momentum * Charge * angular momentum 15. If in the experiment of Wheatstone bridge, the positions of cell and galvanometer are interchanged, then balance point will * Change * Remain unchanged * Depend on the internal resistance of cell and resistance of galvanometer * None of these 16. Column-I gives certain physical terms associated with flow of current through a metallic conductor. Column-II gives some mathematical relations involving electrical quantities. Match Column-I and Column-II with appropriate relations. | Column I | Column II | |---|---| | Relaxation Time | (a) ne²v_d | | Drift Velocity | (b) m/ne²ρ | | Current Density | (c) n e * v_d | | Electrical Resistivity | (d) τ | * (i)-(d), (ii)-(c), (iii)-(b), (iv)-(a) * (i)-(c), (ii)-(d), (iii)-(a), (iv)-(b) * (i)-(a), (ii)-(d), (iii)-(b), (iv)-(c) * (i)-(b), (ii)-(a), (iii)-(c), (iv)-(d) 17. The resistance of a wire is R Ω. If it is melted and stretched to n times its original length, its new resistance will be * R/n * nR * R/n² * n²R 18. Statement I: When a wire is not connected to battery, then no current flows. Statement II: In the absence of electric field free electrons moves randomly or does not move in particular direction. * Both Statements I and Statement II are true and the Statement II is a correct explanation of the Statement I. * Both Statements I and Statement II are true but Statement II is not a correct explanation of the Statement I. * Statement I is true but the Statement II is false. * Statement I and Statement II both are false. 19. Which of the following is different from the others? * volt-ohm^-1 * ampere ohm * volt-ampere * joule second^-2 20. When a steady current flows through a metal conductor of non-uniform cross-section, then drift velocity is * Independent of area of cross-section * Directly proportional to the area of cross-section * Inversely proportional to the area of cross-section * Inversely proportional to the square of area of cross-section 21. Consider a thin square sheet of side L and thickness t, made of a material of resistivity p. The resistance between two opposite faces, shown by the shaded areas in the figure is * Directly proportional to t * Directly proportional to L * Independent of t * Independent of L. ## FILL IN THE BLANKS * In a current carrying conductor the net charge is **zero**. * The magnitude of the drift velocity per unit electric field is **mobility**. * The SI unit of **electric resistivity** is Ωm. * The resistivity of certain metals or alloys drops to zero when they are cooled below a certain temperature, this phenomenon is known as **superconductivity**. * The Kirchhoff's loop rule is based on law of conservation of **energy**. # ELECTROSTATIC POTENTIAL AND CAPACITANCE ## MULTIPLE CHOICE QUESTIONS 1. Name the physical quantity whose SI unit is joule per coulomb. * Power * electric field * electric potential * dipole moment 2. **eV** is a unit of energy. * V * Vm * Vm^-1 * eV 3. Equal charges are given to the two spheres of different radii. The potential will: * Be more on bigger sphere * Be more on smaller sphere * Be equal on both the spheres * Depend on the nature of the materials of the spheres 4. For linear dielectrics, the ratio of dielectric polarisation to the applied electric field is equal to * Mobility * Dipole moment * ε × Susceptibility * Permittivity 5. The dimension of electric polarisation is given by * [L^-1AT] * [LAT] * [ML^-1A^-1T^-3] * [M^-1L^-2A²T^-1] 6. The electric potential at the surface of a charged spherical shell of radius 10 cm is 20 V. The electric potential at the center of the shell is * Zero * 10 V * 20 V * 30 V 7. The electric field at a point which is very close to the surface of a charged conductor with surface charge density σ is * E = σ / ε₀ * E = σ / 2ε₀ * E = 2σ / ε₀ * E = σ / ε₀ 8. The energy density between the plates of a charged capacitor is given by * CV² * ε₀ E² * ε₀ E² / 2 * QV 9. The potential energy of an electric dipole placed in a uniform electric field is * -p.Ε * -p × E * CV² * σ / ε₀ * E² 10. An electric dipole is placed in a uniform electric field. The dipole moment makes an angle θ with the electric field. For what angle θ is the potential energy of the dipole maximum? * θ = 0° * θ = 45° * θ = 90° * θ = 180° 11. Capacitance of a capacitor is defined as C = q/V. A factor on which capacitance of the capacitor depends is: * Charge q * Potential deference V * Geometry of the conductor * all of the above 12. Capacity of a parallel plate capacitor can be increased by * increasing the distance between the plates * increasing the thickness of the plates * decreasing the area of the plates * decreasing the distance between the plates 13. The potential energy of a capacitor is stored in the **electric field** between the plates of the capacitor. * electric charges * electric field * magnetic field * current 14. Which of the following correctly describes the behavior of polar and nonpolar dielectrics in an electric field? * Both polar and nonpolar dielectrics have permanent dipole moments, but only nonpolar dielectrics align in an external field. * Polar dielectrics align their dipole moments with the external field, while in the case of nonpolar dielectrics a dipole moment is induced in response to the field. * Nonpolar dielectrics align their permanent dipole moments in an external field, while polar dielectrics remain unaffected. * Polaectrics and nonpolar dielectrics behave identically in the presence of an electric field, showing no difference in polarization. 15. An electric dipole is placed inside an insulating spherical shell. Pick the wrong statement. * Net charge enclosed by the shell is zero * Sphere acts as equipotential surface. * Electric flux through the sphere is zero. * Electric field is not uniform across the surface of the spherical shell. 16. The following graphs show the variations of two physical quantities with distance 'r' from the center of a uniformly charged spherical shell. Identify the graphs. * First graph shows variation of E versus r and second is V versus r * First graph shows variation of V versus r and second is E versus r * Both graphs shows the variation of V versus r * Both graphs shows the variation of E versus r 17. Statement 1: The electric field inside a conductor is zero. * Both statements are correct and Statement 2 is the correct explanation for the Statement 1. * Both statements are correct and Statement 2 is not correct explanation for the Statement 1. * Statements 1 is correct and Statement 2 is wrong * Statements 1 is wrong and Statement 2 is correct 18. An imaginary sphere radius R is drawn around a charge Q, keeping the charge Q at its center. The work required to move a test charge q from point A to point B is * q(2R) * qVA * zero * qVB 19. Consider the following statements: * Both statements are correct and Statement 2 is the correct explanation for the Statement 1. * Both statements are correct and Statement 2 is not the correct explanation for the Statement 1. * Statements 1 is correct and Statement 2 is wrong * Statements 1 is wrong and Statement 2 is correct 20. The equivalent capacitance of the combination is * ½ * (C₁ + C₂) * (C₁*C₂)/ (C₁ + C₂ * (C₁ + C₂ + C)/ (C₁*C₂) * (C₁*C₂)/ (C₁ + C₂ + C) ## FILL IN THE BLANKS: * The electric potential at the surface of a charged spherical shell is **constant**. * **Electric dipole** is the potential energy of an electric dipole, when dipole moment p is perpendicular to electric field E is. # CURRENT ELECTRICITY ## MULTIPLE CHOICE QUESTIONS: 1. The SI unit of current is * coulomb * ampere * newton * farad 2. When no current is passed through a conductor, * the free electrons do not move * the average speed of a free electron over a large period of time is not zero * the average velocity of a free electron over a large period of time is zero * the average of the velocities of all the free electrons at an instant is non zero 3. In the absence of an electric field, the mean velocity of free electrons in a conductor at absolute temperature (T) is * Zero * independent of T * proportional to T * proportional to T² 4. Ohm's law is valid when the temperature of conductor is * very low * very high * constant * varying 5. In the equation J * B = C, J is the current density, C is the electric field, Then B is * resistivity * conductivity * resistance * potential difference 6. Which of the following is non-ohmic resistance? * Lamp filament * Copper wire * Carbon resistor * Diode 7. The relaxation time in conductors * increases with the increase of temperature * decreases with the increase of temperature * it does not depend on temperature * all of sudden changes at 400 K 8. With increase in temperature the conductivity of * semiconductors increases and metals decreases. * metals increases and of semiconductor decreases. * in both metals and semiconductors increases. * in both metal and semiconductor decreases. 9. Drift velocity of electrons is due to * motion of conduction electrons due to random collisions. * motion of conduction electrons due to electric field E * repulsion to the conduction electrons due to inner electrons of ions. * collision of conduction electrons with each other. 10. Constantan wire is used for making standard resistance, because it has * high melting point * low specific resistance * high specific resistance * negligible temperature coefficient of resistance 11. The resistivity of a wire * increases with the length of the wire * decreases with the area of cross-section * decreases with the length and increases with the cross-section of wire * none of the above statement is correct 12. n identical cells of each emf E and internal resistance r are connected in series. An external resistance R is connected in series with this combination. The current through R is * RE / (R + nr) * RE / (R + r) * E / (R + nr) * nE / (R + r) 13. If the terminals of a cell are connected to an external resistance then the potential difference across its terminals is * more than emf of the cell * less than emf of the cell * equal to emf of the cell * equal to potential drop across its internal resistance 14. Kirchhoff's first law, i.e., ΣI = 0 at a junction, deals with the conservation of * Energy * Momentum * Charge * angular momentum 15. If in the experiment of Wheatstone bridge, the positions of cell and galvanometer are interchanged, then balance point will * Change * Remain unchanged * Depend on the internal resistance of cell and resistance of galvanometer * None of these 16. Column-I gives certain physical terms associated with flow of current through a metallic conductor. Column-II gives some mathematical relations involving electrical quantities. Match Column-I and Column-II with appropriate relations. | Column I | Column II | |---|---| | Relaxation Time | (a) ne²v_d | | Drift Velocity | (b) m/ne²ρ | | Current Density | (c) n e * v_d | | Electrical Resistivity | (d) τ | * (i)-(d), (ii)-(c), (iii)-(b), (iv)-(a) * (i)-(c), (ii)-(d), (iii)-(a), (iv)-(b) * (i)-(a), (ii)-(d), (iii)-(b), (iv)-(c) * (i)-(b), (ii)-(a), (iii)-(c), (iv)-(d) 17. The resistance of a wire is R Ω. If it is melted and stretched to n times its original length, its new resistance will be * R/n * nR * R/n² * n²R 18. Statement I: When a wire is not connected to battery, then no current flows. Statement II: In the absence of electric field free electrons moves randomly or does not move in particular direction. * Both Statements I and Statement II are true and the Statement II is a correct explanation of the Statement I. * Both Statements I and Statement II are true but Statement II is not a correct explanation of the Statement I. * Statement I is true but the Statement II is false. * Statement I and Statement II both are false. 19. Which of the following is different from the others? * volt-ohm^-1 * ampere ohm * volt-ampere * joule second^-2 20. When a steady current flows through a metal conductor of non-uniform cross-section, then drift velocity is * Independent of area of cross-section * Directly proportional to the area of cross-section * Inversely proportional to the area of cross-section * Inversely proportional to the square of area of cross-section 21. Consider a thin square sheet of side L and thickness t, made of a material of resistivity p. The resistance between two opposite faces, shown by the shaded areas in the figure is * Directly proportional to t * Directly proportional to L * Independent of t * Independent of L. ## FILL IN THE BLANKS * In a current carrying conductor the net charge is **zero**. * The magnitude of the drift velocity per unit electric field is **mobility**. * The SI unit of **electric resistivity** is Ωm. * The resistivity of certain metals or alloys drops to zero when they are cooled below a certain temperature, this phenomenon is known as **superconductivity**. * The Kirchhoff's loop rule is based on law of conservation of **energy**. # MOVING CHARGES AND MAGNETISM ## MULTIPLE CHOICE QUESTIONS 1. Who concluded that moving charges or currents produces a magnetic field? * J. C. Maxwell * H. C. Oersted * J. A. Fleming * J. C. Bose 2. When a magnetic compass needle is carried nearby to a straight wire carrying current, then * the straight wire cause a noticeable deflection in the compass needle. * the alignment of the needle is tangential to an imaginary circle with straight wire as its centre and has a plane perpendicular to the wire * both (1) and (2) are correct * neither (1) nor (2) is correct 3. If a current I is flowing in a straight wire parallel to x axis and magnetic field is there along the y axis then * The wire experiences force in x direction * The wire experiences force in y direction * The wire experiences no force * The wire experiences force in z direction 4. A strong magnetic field is applied on a stationary electron. Then the electron * moves in the direction of the field. * remains stationary. * moves perpendicular to the direction of the field * moves opposite to the direction of the field. 5. The radius of the circle described by a charged particle moving perpendicular to a uniform magnetic field depends on * its mass only * its velocity only * both mass and velocity * neither mass nor velocity 6. The frequency of rotation of the charge particle in a uniform magnetic field is independent of * velocity of the particle * charge of the particle * mass of the particle * strength of the magnetic field 7. Which of the following statements is not true regarding Biot-Savart's law, * the magnetic field is proportional to the length of the current element, * the magnetic field is proportional to the current through the current element * the magnetic field is inversely proportional to the distance of the point * the magnetic field is proportional to the sine of the angle between the current direction and the line joining the current element and the point 8. The value of permeability of free space is * 4π × 10^-7 H/m * 9 x 10⁹ Nm²/C² * 8.854 × 10^-12 F/m * 3 × 10⁸ m/s 9. A long straight wire carrying a current induced magnetic induction at any place that is * proportional to the distance from the wire * independent of distance. * inversely proportional to the distance from the wire * inversely proportional to the square of the distance from the wire 10. An electron is projected with uniform velocity along the axis of a current carrying long solenoid. Which of the following is true? * The electron will be accelerated along the axis. * The electron path will be circular about the axis. * The electron will experience a force at 45° to the axis and hence execute a helical path. * The electron will continue to move with uniform velocity along the axis of the solenoid. 11. If the beams of electrons and protons move parallel to each other in the same direction, then they * Attract each other * Repel each other * No relation * Neither attracts nor repel. 12. A rectangular coil carrying current is placed in a non-uniform magnetic field. On the coil the total * force is non-zero * force is zero * torque is zero * none of these 13. A conducting circular loop of radius carries a constant current I. It is placed in a uniform magnetic field B, such that B is perpendicular to the plane of the loop. The magnetic force acting on the loop is * IB * 2πIB * Zero * πrIB 14. In a moving coil galvanometer the deflection (Θ) on the scale by a pointer attached to the spring is * NAB / kI * NAB / kl * kIB / NA * kI / NAB 15. Resistance of an ideal ammeter is * Infinity * 100 Ω * Zero * 1 Ω 16. A charged particle moves