Physics MCQs for Class 12 – Online Test Physics MCQs for Class 12 Total Questions - 40Total Marks - 40Time - 2 Hours 1 / 40 SI unit of electrical capacitance is: stat-farad farad coulomb stat-coulomb 2 / 40 Which of the following remains same while two capacitors are joined in series: Charge Potential Charge and Potential both Neither Charge nor Potential 3 / 40 A parallel plate capacitor is charged then the separation between the plates is increased. The potential difference between the plates will be: Increased Decreased Remains unchanged Becomes zero 4 / 40 Which of the following is not a unit of electrical capacitance: farad coulomb/volt volt coulomb2/joule 5 / 40 Potential of earth is: zero positive negative none of these 6 / 40 A, B and C are three hollow spherical conductors. They have some positive charge. C is smallest and A is biggest, then: The potential of all conductors will be same The potential of A will be highest The potential of B will be highest The potential of C will be highest 7 / 40 Unit of electric potential is : coulomb farad volt ohm 8 / 40 Magnetic effect of electric current was discovered by: Fleming Oersted Faraday Ampere 9 / 40 Which of the following statement is incorrect: The resistance of an ideal ammeter is infinite Resistance of an ideal ammeter is zero The torque acting on a coil in uniform magnetic field is maximum when its plane is parallel to the filed The magnetic filed is not uniform at the centre of current carrying coil 10 / 40 The resistance of a galvanometer is RG, Resistance of ammeter is RA, and that of voltmeter is RV, which of the following statement is correct: RG>RA>RV RG<RA<RV RA<RG<RV RA=RG=RV 11 / 40 An electric circuit : Ammeter is connected in series and voltmeter in parallel Ammeter is connected in parallel and voltmeter in series Ammeter and voltmeter both are joined in series Ammeter and voltmeter both are joined in parallel 12 / 40 I ampere current is flowing through a wire of length 'l'. It is placed parallel to uniform magnetic field. The work done on it will be : 1/2 IBl 2Ibl zero 2Bl 13 / 40 When a current is made to flow through a conductor then it produces: Only electric field Only magnetic field Electric and magnetic field both None of these 14 / 40 A moving charge produces: Only electric field Only magnetic field Electric and magnetic field both None of these 15 / 40 A current carrying coil acts as magnetic dipole. If area of coil is A and magnetic moment is M, then current flowing through the coil is: M/A A/M MA A2M 16 / 40 Magnetic field is not produced by: A charge in uniform motion A charge at rest An accelerating charge A deaccelerating charge 17 / 40 In the position of null deflection: No current flows through galvanometer Current flows through galvanometer due to primary circuit Current flows through due to secondary circuit Nothing can be said 18 / 40 The SI unit of potential gradient is: ohm/cm volt volt x cm volt / metre 19 / 40 Internal resistance of cell depends upon: Area of plates Distance between the plates Concentration of electrolyte All of the above 20 / 40 Unit of specific resistance is: ohm ohm-1 ohm metre ohm-1metre-1 21 / 40 The specific resistance of a wire depends upon the: Length Diameter Mass Material 22 / 40 The order of drift velocity of free electrons in m/sec. is : 104 10-4 106 10-6 23 / 40 The relaxation time of free electrons in metals: Increases with increase in temperature Decreases with increase in temperature Does not depend upon temperature None of these 24 / 40 Two resistances R1 and R2 are joined in parallel. If their equivalent resistance is R then: R<R1 R<R2 Both R<R1 and R<R2 R>R1 or R>R2 25 / 40 The resistance of a conductor does not depend upon: Length of conductor Cross-section of wire Nature of material conductor Applied potential difference 26 / 40 Which of the following relation is not correct: Resistance-ohm Charge-coulomb Electric current-ampere Specific resistance-per0C 27 / 40 Ampere is unit of: Electric current Electric charge Potential difference Dielectrons 28 / 40 The flow of electric current through a conductor is: Flow of positive icons Flow of free electrons Flow of molecules None of these 29 / 40 The intensity of electric field (E) at a distance 'r' from the point charge Q is: E ∝ r E ∝ 1/r2 E ∝ 1/r E ∝ 1/r3 30 / 40 The number of electrons in 1 coulomb are: 5.46x1029 6.25x1018 1.6x10-19 9.0x1011 31 / 40 The dielectric constant of air is: 8.885x10 1 Infinite None of these 32 / 40 The unit of intensity of electric field is: newton/coulomb coulomb/newton joule/coulomb coulomb/joule 33 / 40 When a dielectric medium is placed between the two charges instead of vacuum then the force between them: Decreases Increases Remains unchanged None of these 34 / 40 If a spherical shell is given positive charge then: The charge will be distributed uniformly inside and outside Entire charge will be distributed uniformly over upper surface Entire charge will be distributed uniformly over inner surface On the outer surface the positive charge and in the inner surface the negative charge will distribute 35 / 40 The force of repulsion between the two point charges when they are kept at 'r' distance apart from each other is F. If the distance between them is doubted then the force of repulsion will be: F/4 F/2 3/4 F F 36 / 40 Unit of ϵo is : Coulomb/newton-metre newton-metre2/coulumb2 coulumb2/newton-metre2 None of these 37 / 40 The electric field due to a dipole is: Zero at the centre of dipole Zero at each point on equatorial line Perpendicular to the dipole axis at each point on equatorial line Parallel to the dipole axis at each point on equatorial line 38 / 40 Two point charges are first placed in air and then kept in a medium of dielectric constant K as same distance. The ratio of force acting between the charges in the above two conditions be : 1:K K:1 4K:1 1:3K 39 / 40 The force acting between two charges q1 and q2 is The force: Depends only on the units Depends on the medium between the charges Depends on both the units and medium between the charges Does not depends upon the both 40 / 40 If an electron is removed from an isolated body then the charge on that body will be : Zero -1.6x10-19C +1.6x10-19C None of these Your score is 0% Restart quiz Share This इन्हे भी पढ़े Class 12 Physics MCQs – Reflection of Light Online Test Post navigation Previous Previous post: Class 10th Math – Chapter 8 & 9 – Trigonometry (त्रिकोणमिति )Next Next post: MP Patwari Syllabus 2023 | Updated MP Patwari Exam Pattern 2023