12th Physics Full Book MCQs (educatedzone.com) PDF
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This document is a collection of multiple-choice questions (MCQs) covering various physics topics, including electrostatics, current electricity, and electromagnetism. It is suitable for 12th-grade students studying physics.
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www.educatedzone.com F.Sc. Physics (2nd Year) Multiple Choice Questions Chapter # 12: Electrostatics Chapter # 13: Current Electricity Chapter # 14: Electromagnetism Chapter # 15: Electromagnetic Induction Chapter # 16: Alternating Current Chapter # 17: Physics of Solids Chapt...
www.educatedzone.com F.Sc. Physics (2nd Year) Multiple Choice Questions Chapter # 12: Electrostatics Chapter # 13: Current Electricity Chapter # 14: Electromagnetism Chapter # 15: Electromagnetic Induction Chapter # 16: Alternating Current Chapter # 17: Physics of Solids Chapter # 18: Electronics Chapter # 19: Dawn of Modern Physics Chapter # 20: Atomic Spectra Chapter # 21: Nuclear Physics www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 12 CHAPTER # 12: ELECTROSTATICS 1. Coulomb’s law is only applicable for 8. The electric field created by positive a) Big charges charge is: b) Small charges a) Radially outward c) Point charges b) Zero d) Any charges c) Circular d) Radially inward 2. The force exerted by two charged bodies on one another, obeys Coulomb’s law 9. The value of relative permitivity for all the provided that dielectrics is always: a) The charges are not too small a) Less than unity b) The charges are in vacuum b) Greater than unity c) The charges are not too large c) Equal to unity d) The linear dimension of charges is d) Zero much smaller than distance between them 10. Photo-copier and inkjet printers are the applications of: 3. The constant K in Coulomb’s Law a) Electronics depends upon b) Magnetism c) Electrostatics a) Nature of medium d) Thermodynamics b) System of units c) Intensity of charge 11. Selenium is a conductor material when d) Both a & b exposed to ________ a) Light 4. A unit if elelctric charge is: b) Dark a) Volt c) Mono chromatic light b) Henry d) None of these c) Coulomb d) Weber 12. Selenium is an a) Insulator 5. Presence of dielectric always: b) Conductor a) Increases the electrostatic force c) Semiconductor b) Decreases the electrostatic force d) Photoconductor c) Does not effect the electrostatic force d) Doubles the electrostatic force 13. In an inkjet printer, the charged ink drops are diverted by the deflection plates 6. The S.I unit of permitivity is: 2 a) 𝑁𝑚 𝐶 2 a) Towards the charging electrodes 2 b) 𝐶 𝑁𝑚 2 b) Towards the gutter c) Towards a blank paper on which the c) 𝑁𝑚 𝐶 2 print is to be taken 2 d) 𝑁𝑚 𝐶 d) In inkjet printer ink cannot be charged 7. The lines which provide information about 14. The electric field produced due to negative the electric force exerted on charged charge is always: particles are: a) Radially outward a) Magnetic field lines b) Radially inward b) Electric field lines c) Circular c) Tangent lines d) Zero d) Curved lines 1 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 12 15. The force experience by a unit positive 22. Electric flux is defined as: charge placed at a point in an electric field a) 𝜙 = 𝐀. 𝐁 is called: b) 𝜙 = 𝐄 × 𝐀 a) Coulomb’s force c) 𝜙 = 𝐄. 𝐀 b) Faraday’s force 𝐄 d) 𝜙 = 𝐀 c) Lorentz’s force d) Electric field intensity 23. When vector area is held perpendicular to the field lines, then the magnitude of 16. Of the following quantities, the one that is vector in character is an electric flux is: a) Negative b) Maximum a) Electric Charge b) Electric Field Intensity c) Minimum c) Electric Energy d) Zero d) Electric Potential Difference 24. When vector area is held parallel to 17. Electric field intensity is also known as electric field lines, the the magnitude of electric flux is: a) Electric potential a) Maximum b) Electric flux c) Potential gradient b) Minimum d) None c) Either maximum or minimum d) Negative 18. Potential gradient is defined as ∆𝐸 25. The SI unit of electric flux is: a) ∆𝑉 a) 𝑁𝑚𝐶 −1 ∆𝐸 b) − ∆𝑉 b) 𝑁𝑚 2 𝐶 −1 ∆𝑟 c) 𝑁𝑚𝐶 −2 c) ∆𝑉 d) 𝑁𝑚 2 𝐶 −2 ∆𝑉 d) − 26. The magnitude of the electric field inside ∆𝑟 oppositely charged plates, having uniform 19. The SI unit of E are: surface charge density 𝜎, is: a) 𝑛𝑒𝑤𝑡𝑜𝑛 𝑚𝑒𝑡𝑒𝑟 a) 𝜎 𝜀0 b) 𝑛𝑒𝑤𝑡𝑜𝑛 𝑐𝑜𝑢𝑙𝑜𝑚𝑏 b) 𝜎 2𝜀 0 𝑞 c) 𝑛𝑒𝑤𝑡𝑜𝑛 𝑎𝑚𝑝𝑒𝑟𝑒 c) 𝜀0 𝑟 d) 𝑛𝑒𝑤𝑡𝑜𝑛 × 𝑚𝑒𝑡𝑒𝑟 d) 𝜎 2𝜀 𝑟 0 20. The electric intensity is expressed in unit 27. The electric intensity near an infinite plate of N/C or of positive charge will be: 𝑞 a) Volts a) 𝜀0 b) Walt b) 𝜎 c) Joules 2𝜀0 𝑞 d) V/m c) 𝐴 d) 𝜎 𝜀0 21. The unit 𝑉𝑚 −1 is equivalent to: a) 𝑁𝐶 −1 28. If a charged body is moved agaist the b) 𝑁𝐶 electric field, it will gain: c) 𝑁𝐶 𝑚 −1 a) Potential energy d) 𝑁𝑚𝐶 −1 b) Kinetic energy c) Mechanical energy d) None of these 2 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 12 29. One volt is 37. The equation for the stokes law is a) One joule per coulomb a) 6𝜋𝜂𝑟 b) One dyne per coulomb b) 6𝜋𝜂𝑟𝑣 c) One Newton per coulomb c) 6𝑟𝑣 d) One watt per second d) 8𝜋𝜂𝑟𝑣 30. Absolute potential difference, due of point 38. The charge determined by the Millikan’s charge of 1C at a distance of 1m is given experiment is by: qvd a) 9 × 106 𝑣𝑜𝑙𝑡𝑠 a) q m b) 9 × 107 𝑣𝑜𝑙𝑡𝑠 c) 9 × 108 𝑣𝑜𝑙𝑡𝑠 qvd b) q d) 9 × 109 𝑣𝑜𝑙𝑡𝑠 g mgd 31. A charge of 0.01 C accelerated through a c) g p.d of 1000 V acquires K.E v a) 10 J d) None b) 100 J c) 200 J 39. Capacitors may be considered as a device d) 400 eV for a) Storing energy 32. 1 joule =__________ b) Increasing resistance c) Decreasing resistance a) 6.25 × 1018 𝑒𝑉 d) None b) 6.25 × 10−18 𝑒𝑉 c) 1.6 × 10−19 𝑒𝑉 40. The medium used b/w the plates of d) 9.1 × 10−31 𝑒𝑉 capacitor is called 33. One electron volt is equal to a) Polarization a) 6.25 × 1018 𝐽 b) Dielectric b) 6.25 × 10−18 𝐽 c) Insulators c) 1.6 × 10−19 𝐽 d) Medium d) 9.1 × 10−31 𝐽 41. Capacity of a capacitor depends upon 34. How many electron will have a charge of a) Size of plate one coulomb? b) Distance b/w plates a) 6.2 × 1018 c) Nature of dielectric b/w plates b) 6.2 × 1019 d) All of above c) 5.2 × 1018 d) 5.2 × 1019 42. Farad is defined as: 𝐶 a) 35. Gravitational force between two objects 𝑉 𝐴 does not depends on: b) 𝑉 a) Force 𝐶 c) 𝐽 b) Masses 𝐽 c) Distance d) 𝐶 d) Medium 43. The capacitance of a parallel plate 36. The charge on the electron was calculated capacitor is given by: by 𝐴 a) 𝐶 = a) Faraday 𝜀0 𝑑 𝐴𝜀 0 b) J.J. Thomson b) 𝐶 = 𝑑 c) Millikan 𝜀0 𝑑 c) 𝐶 = 𝐴 d) Einstein 𝑑 d) 𝐶 = 𝜀 𝐴 0 3 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 12 44. The expression of energy stored in a 47. The ratio of Cvac and Cmed is equal to capacitor is given by: a) 𝜀𝑟 a) 𝐸 = 𝐶𝑉 2 b) 𝜀 1 1 𝑟 b) 𝐸 = 𝐶𝑉 2 c) 𝜀0 2 1 1 c) 𝐸 = 2 𝐶 2 𝑉 d) 𝜀 1 0 d) 𝐸 = 2 𝐶𝑉 2 45. Unit of energy density of electric field is: 48. During charging of a capacitor, the ratio of a) J C−1 instantaneous charge and maximum b) J V −1 charge on plates of capacitors at t = RC is c) J m−3 d) J F −3 a) 36.8% 46. The term “RC” has same unit as that of: b) 63.2% a) Potential c) 20% b) Capacitance d) 30% c) Energy d) Time Q. No. Ans. Q. No. Ans. Q. No. Ans. 1 c 17 c 33 c 2 d 18 d 34 a 3 d 19 b 35 d 4 c 20 d 36 c 5 b 21 a 37 b 6 b 22 c 38 c 7 b 23 d 39 a 8 a 24 a 40 b 9 b 25 b 41 d 10 c 26 a 42 a 11 a 27 b 43 b 12 d 28 a 44 b 13 b 29 a 45 c 14 b 30 d 46 d 15 d 31 a 47 b 16 b 32 a 48 b 4 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 13 CHAPTER # 13: CURRENT ELECTRICITY 8. The heat produced by passage of current through resistor is: 1. One coulomb per second is equal to a) 𝐻 = 𝐼2 𝑅𝑡 a) Joule b) 𝐻 = 𝐼𝑅2 𝑡 b) Volt 𝐼2 c) 𝐻 = 𝑅𝑡 c) Ampere 𝐼 d) Walt d) 𝐻 = 𝑅𝑡 2. In the metallic conductor the current is due 9. Current can be measured by using: to flow of ______ charge a) Heating effect a) Positive b) Magnetic effect b) Negative c) Chemical effect c) Proton d) None of these d) None 10. In liquids and gases, the current is due to 3. Conventional current flow from the motion of : a) Point of higher potential to point of a) Negative charges lower potential b) Positive charges b) Point of lower potential to point of c) Neutral particles higher potential d) Both negative and positive charges c) Point of lower potential to point of lower potential 11. When electricity passes through the liquid, d) None then process is called: a) Electro late 4. In the thermocouple the heat energy is b) Electrolysis converted into c) Electro-conductor a) Mechanical energy d) None b) Electric energy c) Magnetic energy 12. Magnetic effect of current is utilized in d) None a) Iron b) Thermocouple 5. The heating effect of current utilized in c) Measurement of current a) Iron d) None b) Tube light c) Fan 13. The VI-graph of Ohm’s law is: d) Motor a) Hyperbola b) Ellipse 6. Through an electrolyte, electric current is c) Parabola passed due to drift of d) Straight a) Free electrons b) Positive and negative ions 14. Mathematical form of ohm’s law is c) Free electrons and holes a) I = VR d) Protons b) I = V/R c) I = R/V 7. Joule law can be expressed as d) R = IV a) 𝐻 = 𝐼2 𝑅𝑡 b) 𝐻 = 𝐼𝑅2 𝑡 15. Ohm’s law is valid for only current 𝐼2 flowing in c) 𝐻 = 𝑅𝑡 𝐼 a) Conductors d) 𝐻 = 𝑅𝑡 b) Transistors c) Diodes d) Electric Areas 1 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 13 16. The proportionality constant between 24. Thermistor can be used for the accurate current and potential difference is: measurement of a) 𝜌 a) Voltage b) 𝑅 b) Resistance c) 𝐶 c) Temperature d) 𝑉 d) Heat 17. 1 ohm is defined as: 𝑉 25. The maximum power delivered by battery a) 𝐶 𝑉 is: b) 𝐸2 𝐴 𝐶 a) 𝑃𝑚𝑎𝑥 = 4𝑟 c) 𝑉 b) 𝑃𝑚𝑎𝑥 = 4𝑟𝐸 2 𝑉 d) c) 𝑃𝑚𝑎𝑥 = 𝑉𝐼𝑇 𝐴 d) 𝑈𝑛𝑙𝑖𝑚𝑖𝑡𝑒𝑑 18. In series circuit the net resistance is a) Algebraic Sum of all resistance 26. If the length and diameter of conductor is b) Sum of reciprocals of all resistances in double, the resistance is circuit a) Remain same c) Remain constant b) Double d) None c) Half d) Four times 19. The reciprocal of resistivity is called a) Resistance 27. A wire of uniform cross-section A and b) Conduction length L is cut into two equal parts. The c) Conductivity resistance of each part becomes: d) None a) Double b) Half 20. The unit of conductivity is c) 4 times a) Ω. m d) ¼ times b) (Ω.m)-1 c) Ω.m-1 28. The fractional change in resistivity per d) None Kelvin a) Co-efficient in resistance 21. A wire of resistance R is cut into two b) Co-efficient of resistivity equal parts, its resistance becomes R/2. c) Resistance What happens to resistivity? d) None a) Double b) Same 29. In the carbon resistor their value can be c) Half find by their d) One forth a) Wires b) Terminals 22. When temperature increases, the c) Color Bands resistance of conductor: d) Spots a) Increases 30. The third band is written in the form of b) Decreases power of c) Remains constant a) 2 d) Vanishes b) 6 c) 8 23. Heat sensitive resistors are called d) 10 a) Resistors b) Capacitors 31. The numerical value of black color is: c) Thermisters a) 3 d) Inductors b) 2 c) 1 d) 0 2 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 13 32. The color code for the color Grey is 40. Which electric bulb has the least a) 7 resistance? b) 8 a) 60 watts c) 9 b) 100 watts d) 5 c) 200 watts 33. The colors of strips on a certain carbon d) 500 watts resistor from extreme left are yellow, black and red respectively. Its resistance 41. An electric heater 220V, 440W has a is: resistance a) 4 𝑘Ω a) 2 Ω b) 400 Ω b) 110 Ω c) 40 Ω c) 0.5 Ω d) 40 𝑘Ω d) 20 Ω 34. If the tolerance color is gold then it value 42. Kirchhoff’s first rule is: is a) 𝑉=0 a) ± 2% b) 𝑅=0 b) ± 4% c) 𝐼=0 c) ± 5% d) 𝑇=0 d) ± 6% 43. Kirchhoff’s first rule is based on 35. Tolerance for silver band is: conservation of: a) ±5% a) Energy b) ±10% b) Voltage c) ±15% c) Charge d) ±20% d) Mass 44. The algebraic sum of all the current at 36. A rheostat can be used as a junction is zero, is Kirchhoff’s a) Variable resistor a) 1st law b) Potential divider b) 2nd law c) Both a and b c) 3rd law d) None of these d) 4th law 45. The algebraic sum of voltages changes 37. The wire used in Rheostat is made from around a closed circuit or loop is zero, is a) Constantan Kirchhoff’s b) Nichrome a) 1st law c) Manganin b) 2nd law d) Tungston c) 3rd law d) 4th law 38. The S.I unit of emf is same as: 46. An ideal voltmeter would have an infinite a) Work a) Current b) Energy b) Voltage c) Power c) Resistance d) Potential Difference d) None of these 39. The terminal potential difference of a 47. The emf of two cells can be compared by battery of internal resistance “r” and emf a) AVO meter “𝜀” is: b) Voltmeter a) 𝑉 = 𝜀 + 𝐼𝑟 c) Potentiometer b) 𝑉 = 𝜀 − 𝐼𝑟 d) Galvanometer 𝜀−𝑟 c) 𝑉 = 𝐼 𝐼 d) 𝑉 = 𝜀−𝑟 3 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 13 48. An accurate measurement of emf of a cell is made by a) A voltmeter b) An ammeter c) A potentiometer d) All of them 𝜀1 49. The ratio of emf of two cells 𝜀2 , is equal to 𝑙 a) 1 𝑙 2 b) 1 ∶ 2 𝑙 c) 2 𝑙 1 d) 2 ∶ 1 Q. No. Ans. Q. No. Ans. Q. No. Ans 1 c 18 a 35 b 2 b 19 c 36 c 3 a 20 b 37 c 4 b 21 b 38 d 5 a 22 a 39 b 6 b 23 c 40 d 7 a 24 c 41 b 8 a 25 a 42 c 9 b 26 c 43 c 10 d 27 b 44 a 11 b 28 b 45 b 12 c 29 c 46 c 13 d 30 d 47 c 14 b 31 d 48 c 15 a 32 c 49 a 16 b 33 d 17 d 34 c 4 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 14 CHAPTER # 14. ELECTROMAGNETISM 8. When a small resistance is connected 1. The units of magnetic field B, in system parallel to the galvanometer, the international is: resulting circuit behaves as: a) Weber a) Voltmeter b) Tesla b) Wheatstone bridge c) Gauss c) Ammeter d) Newton d) Potentiometer 2. One tesla (T) is: 9. The anode in the CRO is: a) 1𝑇 = 1𝑁 𝐴 𝑚 −1 a) Control number of electrons b) Control the brightness of spot b) 1𝑇 = 1𝑁 𝐴−1 𝑚 −1 formed c) 1𝑇 = 1𝑁 𝐴 𝑚 c) Accelerates and focus the beam d) 1𝑇 = 1𝑁 𝑚 𝐴−1 d) At negative potential with respect to cathode 3. The magnetic flux “∅” through an area “A” is: 10. The galvanometer constant in a moving a) ∅ = 𝐁 × 𝐀 coil galvanometer is given by: b) ∅ = 𝐁. 𝐀 𝑁𝐵 a) 𝐾 = 𝐶𝐴 c) ∅ = 𝐀 × 𝐁 𝐶 d) 𝑁𝑜𝑛𝑒 𝑜𝑓 𝑡𝑒𝑠𝑒 b) 𝐾 = 𝑁𝐴𝐵 𝑁𝐴𝐵 c) 𝐾 = 𝐶 4. One Tesla is also equal to 𝐶𝐴 a) wb.m2 d) 𝐾 = 𝑁𝐵 b) wb.m-2 𝑁 c) wb.m 11. 𝑟=1 𝐁. 𝚫𝐋 = 𝜇0 𝐼 is the relation for: d) None a) Milikan’s law b) Gauss’s law 5. Torque on a current carrying coil is: c) Ampere’s aw d) Lenz’s law a) 𝐵𝐼𝑁𝐴 cos 𝛼 b) 𝐵𝐼𝑁𝐴 sin 𝛼 12. The brightness of spot on CRO screen is c) 𝐵𝐼𝐿 cos 𝛼 controlled by: d) 𝐵𝐼𝐿 sin 𝛼 a) Anodes b) Cathodes 6. The magnetic force is simply a: c) Grid a) Reflecting force d) Plates b) Deflecting force c) Restoring force 13. To measure the current in a circuit, d) Gravitational force ammeter is always connected in: a) Parallel 7. The galvanometer can be made sensitive 𝐶 b) Series if the value of the factor is: c) Sometimes parallel sometimes series 𝐵𝑁𝐴 a) Made large d) Neither series nor parallel b) Made small c) Remains constant 14. If the angle b/w v and B is zero then d) Infinite magnetic force will be a) Max b) Min c) Zero d) None 1 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 14 22. To convert a Weston-type galvanometer 15. A charged particles is projected at an into voltmeter, the series resistance is angle into a uniform magnetic field. given by ________ Which of the following parameter of the 𝑉 a) 𝑅 = 𝐼 charged particle will be affected by 𝑔 𝑉 magnetic field: b) 𝑅 = − 𝑅𝑔 𝐼𝑔 a) Energy 𝑉 b) Momentum c) 𝑅 = 𝑅 − 𝐼𝑔 𝑔 c) Speed d) 𝑁𝑜𝑛𝑒 𝑜𝑓 𝑡𝑒𝑠𝑒 d) Velocity 23. The shape of magnetic field around a 16. Force on a moving charge in a uniform long straight current carrying wire is magnetic field will be maximum, when a) Electrical angle between v and B is: b) Squire a) 0° c) Varies with current b) 30° d) Circular c) 60° 24. The electrons of mass “m” and charge d) 90° “e” is moving in a circle of radius “r” with speed “v” in a uniform magnetic 17. The S.I. unit of magnetic flux is field of strength “B”. then a) Tesla a) 𝑟 ∝ 𝑚 b) Weber b) 𝑟 ∝ 𝐵 c) Joule 1 c) 𝑟 ∝ 𝑣 d) Newton 1 d) 𝑟 ∝ 𝑚 18. Beam of electrons are also called: 25. The toque in the coil can be increased a) Positive rays by increasing b) x-rays a) Number of turns c) cathode rays b) Current and magnetic field d) cosmic rays c) Area of coil d) All of above 19. Tesla is the unit of a) Electric field 26. A current carrying loop, when placed in b) Magnetic field a uniform magnetic field will experience c) Magnetic field intensity a) Electric flux d) Electric field intensity b) Torque c) Magnetic flux 20. It is possible to set a charge at rest into d) Force motion with magnetic field a) Yes 27. The magnetic flux will be maximum if b) No the angle between magnetic field c) Some Time strength and vector area is: d) None a) 0o b) 60o 21. The grid in CRO ________ c) 90o a) Controls the number of electrons d) 180o accelerated by anode b) Controls the brightness of the spot 28. One weber is equal to fall on the screen a) N.A2/A c) Both a and b b) N.m2/A d) Deflects the beam of electrons c) N.A/m d) N.m/A 2 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 14 36. In the galvanometer the current is 29. The waveform of sinusoidal voltage, its proportional to frequency and phase can be found by a) Magnetic field a) CRO b) Electric field b) Diode c) Angle c) Transistor d) None d) Radio 37. When a small resistance is connected in 30. The force on a charge particle moving parallel to the galvanometer it is called parallel to magnetic field is a) Ammeter a) Maximum b) Voltmeter b) Minimum c) AVO meter c) Zero d) None d) None 38. The relation between current “𝐼” and 31. The unit of permeability of free space is deflection “𝜃” in a moving coil a) T.m/A galvanometer is: 1 b) T.m2/A a) 𝐼 ∝ 𝜃 c) T.m/A2 b) 𝐼 ∝ cos 𝜃 d) None c) 𝐼 ∝ sin 𝜃 d) 𝐼 ∝ 𝜃 32. The value of o is 39. To convert a galvanometer into a) 4 x 10-6 voltmeter we connect a resistance in b) 4 x 10-7 a) Series c) 4 x 10-8 b) Parallel d) 4 x 10-9 c) Series or parallel d) None 33. The magnetic induction inside current 40. AVO-meter is used to find carryin solenoid is a) Current a) o nI b) Voltage c) Resistance b) o NL d) All of above c) oN 41. An ideal voltmeter has d) None a) Small resistance b) High resistance 34. F = Fe + Fm is c) Infinite resistance a) Electric force d) None b) Magnetic force 42. A galvanometer can be more sensitive if c) Lorentz force d) None C/BAN is made a) Very large 35. The material used in fluorescent screen b) Very small is c) Unaltered a) Electric d) None b) Magnetic c) Phosphors 43. Ammeter and galvanometer d) None a) Are always connected in series b) Are always connected in parallel c) Both in series and parallel d) None 3 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 14 51. To find the shunt resistance we used 44. The sensitivity of galvanometer is equation directly depends on IgRg a) Magnetic field a) RS = I Ig b) Area of coil c) Number of turns IsRg b) R S = d) All of above I Ig IgRs 45. The dot product of magnetic field c) R S = induction and vector area is called R Ig a) Electric flux IsRs d) R S = b) Magnetic flux I Ig c) Ampere law d) None 52. Ammeter is used to measure: a) Resistance 46. When the number of turns in a solenoid b) Voltage is doubled without any change in the c) Current length of the solenoid its self induction d) Capacitance will be: a) Four times 53. An avo-meter is also called: b) Doubled a) An ammeter c) Halved b) A voltmeter d) None c) A multi.meter d) An ohm-meter 47. The wave form of sinusoidal voltage, its frequency and phase can be found by a) CRO b) Diode c) Transistor d) Radio 48. Voltmeter is used to measure: a) Current b) Resistance c) Temperature d) Potential difference 49. The resistance of a voltmeter should have a very high resistance a) It does not disturb the circuit b) It draws some current c) It same the galvanometer coil d) None of these 50. A voltmeter is always connected in: a) Parallel b) Series c) Perpendicular d) Straight line 4 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 15 CHAPTER # 15. ELECTROMAGNETIC INDUCTION 1. The induced e.m.f. is produce due to a) Motion of coil 8. The inductance is more in self induction b) Motion of magnet in: c) The rate of change of flux a) Air cored coil d) None b) Iron cored coil c) Tungsten cored coil 2. The direction of induced current is always d) None of these so as to oppose the change which causes the current is called: 9. One henry is equal to: a) Faraday’s law a) 1 𝑜ℎ𝑚 × 1 𝑠𝑒𝑐𝑜𝑛𝑑 b) Lenz’s law b) 1 𝑜ℎ𝑚 × 1 𝑚𝑒𝑡𝑒𝑟 c) Ohm’s law c) 1 𝑜ℎ𝑚 × 1 𝑐𝑜𝑢𝑙𝑜𝑚𝑏 d) Kirchhoff’s 1st rule d) 𝑁𝑜𝑛𝑒 𝑜𝑓 𝑡ℎ𝑒𝑠𝑒 3. The energy stored per unit volume inside a 10. A device which converts electrical energy solenoid is calculated by: 1 𝐵2 into mechanical energy is called: a) 2 𝜇0 𝐴𝑙 a) Transformer 1 𝐵2 b) AC generator b) 2 𝜇0 c) DC motor 1 𝜇0 c) 𝐴𝑙 d) DC generator 2 𝐵2 1 𝜇0 d) 2 𝐵2 11. When constant current flows in primary of transformer, then the emf induced across 4. The SI units of induced emf is secondary of transformer is: a) Ohm a) Zero b) Tesla b) Constant c) Henry c) Alternating d) Volt d) Irregular 5. The principle of an alternating current 12. 1 henry generator is based on: a) 1 𝑉 𝐴 𝑠 −1 a) Coulomb’s law b) 1 𝑉 𝑠 𝐴−1 b) Ampere’s law c) 1 𝑉 𝑚 𝐴−1 c) Faraday’s law d) 1 𝑉 𝐴 𝑚−1 d) Lenz’s law 13. A generator converts mechanical energy 6. If velocity of a conductor moving through into a magnetic field B is made zero, then a) Chemical energy motional emf is: b) Light energy a) −𝑣𝐵𝐿 c) Heat energy 𝑣 b) − 𝐵𝐿 d) Electrical energy 𝐵𝐿 c) − 𝑣 14. When a loop of wire is moved across a d) Zero magnetic field, the current is produced in it is called 7. If we make the magnetic field stronger, a) Eddy current the value of induced current is: b) Direct current a) Decreased c) Photo electric current b) Increased d) Induced current c) Vanished d) Kept constant 1 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 15 15. Energy stored in an inductor is: 22. If we increase the resistance of the circuit 1 a) 2 𝐿𝐼 2 containing a coil, the induced e.m.f. will 1 be b) 𝐿𝐼 a) Increase 2 1 2 2 c) 2 𝐿𝐼 b) Decrease 1 c) Remain same d) 2 𝐿𝐼 d) None 16. If fingers of right hand show the direction 23. The self-inductance may be defined by of magnetic field and palm shows the direction of force, then thumb points for: a) L= a) Torque / t b) Voltage / t b) L = c) Current d) Induced emf c) L = 17. Induced electric current can be explained / t using which law a) Gauss’s law d) L = b) Faraday’s law / t c) Ohm’s law d) Ampere law 24. Inductance are measured by a) Coulombs 18. Lenz’s law is consistent with law of b) Amperes conservation of c) Volt a) Mass d) Henry b) Energy c) Charge 25. An over loaded motor draws d) None a) Max. current b) Min. current 19. An inductor is a circuit element that can c) Half store energy in the form of d) None a) Magnetic field b) Electric flux 26. The co-efficient of mutual inductance is c) Electric field equal to ∆𝐼 d) None a) 𝜀 ∆𝑡𝑃 ∆𝑡 20. The negative sign with induced e.m.f. b) 𝜀 ∆𝐼𝑃 is due to c) 𝜀∆𝐼𝑃 ∆𝑡 a) Faraday’s law d) None b) Lenz’s law c) Ampere law 27. Alternating current changes d) None a) Its magnitude as well as direction b) Only direction but not magnitude 21. The relation of motional e.m.f. , when a c) Only magnitude but not direction conductor is move in perpendicular d) None magnetic field, is: a) E=BLV 28. Inductance is measured in: b) E=qBl a) Volt c) E=Blq b) Ampere d) E=qVB c) Henry d) Ohm 2 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 15 29. The instantaneous value of A.C. voltage is 37. The coil which is connected to input of a a) V = Vo sin 2 ft transformer is called: a) Primary b) V = Vo sin 2 ft b) Secondary c) V = Vo sin 2 wt c) Middle d) None d) None 30. The induced e.m.f. in A.C. generator is 38. In the actual transformer, the output is a) VBL sin always a) Equal to input b) NESN sing b) Less then input c) More than input c) NAB sin d) None d) NIAB sin 39. In ideal transformer when applied potential difference is double, the current 31. The back motor effect exist in the is: a) Generator a) Doubled b) Mater b) Tripled c) A.C. Meter c) Halved d) None d) Same 32. The coil used in the generators is called 40. For a good transformer the hysterics loop a) Commutaters are _______ in size. b) Slip rings a) Small c) Armature b) Large d) None c) Zero d) None 33. The back ward generator is called a) Electric motor 41. To minimize the heating effect in the b) A.C. generator transmission lines c) Reverse generator a) High current, low voltage in used d) None b) High voltage, low current in used c) Same voltage and current in used 34. The principle of transformer is d) None a) Amperes law b) Mutual induction 42. Maximum emf generated in a generator is: c) Motional e.m.f. a) 𝜀 = 𝜀0 sin 𝜃 d) None b) 𝜀 = 𝑁𝜔𝐴𝐵 sin 𝜃 35. A transformer is a device which step up or c) 𝜀 = 𝑁𝜔𝐴𝐵 d) None of these stop down a) Energy 43. Induced e.m.f is b) Power a) Directly proportional to change in c) Voltage flux d) All of above b) Directly proportional to rate of change c) of flux 36. An ideal transformer obeys the law of d) Inversely proportional to change of conservation of: flux a) Flux e) None of these b) Momentum c) Emf d) Energy 3 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 15 44. Lenz’s law is in accordance with the law of conservation of: a) Momentum b) Angular momentum c) Energy d) Charge 45. When motor is at its Max. speed the back e.m.f will be a) Maximum b) Zero c) Cannot tell d) None of these 46. The application of mutual induction is a a) Television b) Radio c) D.C. motor d) Transformer 47. The ratio of average induced emf to the rate of change of current in the coil is called: a) Self inductance b) Mutual inductance c) Self inductance d) Mutual inductanc 48. Which of the following is not present in AC generator: a) Armature b) Magnet c) Slip rings d) Commutator 4 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 16 CHAPTER # 16. ALTERNATING CURRENT CIRCUITS 1. The mean value of A.C. over a complete cycle in 9. Which of the following requires a a) Maximum material medium for their propagation: b) Minimum a) Heat waves c) Zero b) X-rays d) None c) Sound waves 2. The inductive reactance is: d) Ultravoilot rays a) 𝑋𝐿 = 𝜔𝐶 b) 𝑋𝐿 = 𝜔𝐿 10. In modulation, low frequency signal is 1 known as: c) 𝑋𝐿 = 𝜔𝐶 a) Loaded signal 1 d) 𝑋𝐿 = b) Fluctuated signal 𝜔𝐿 c) Harmonic signal 3. At high frequency, the current through a d) Modulation signal capacitor of AC circuit will be: a) Large 11. The mutual induction between two coils b) Small depends upon: c) Infinite a) Area of the coils d) Zero b) Number of turns c) Distance between the coils 4. The highest value reached by the d) All of these voltage or current in one cycle is called a) Peak to peak value 12. Pure choke consumes: b) Peak value a) Minimum power c) Instantaneous value b) Maximum power d) Root mean square value c) No power d) Average power 5. If the motor is overloaded, then the magnitude of “back emf”: 13. To construct a step down transformer: a) Increases a) 𝑁𝑆 < 𝑁𝑃 b) Decreases b) 𝑁𝑃 < 𝑁𝑆 c) Constant c) 𝑁𝑆 = 𝑁𝑃 d) Becomes zero d) 𝑁𝑆. 𝑁𝑃 = 1 6. A capacitor is perfect insulator for: 14. Power dissipation in pure inductive or in a) Alternating current a pure capacitive circuit is: b) Direct current a) Infinite c) Both a and b b) Zero d) None c) Minimum d) Maximum 7. The process combining low frequency signal with high frequency radio wave is 15. The practical appllication of called: phenominon of mutual induction is: a) Modulation a) Electrical motor b) Amplification b) Transformer c) Demodulation c) Ac generator d) Resonance d) DC generator 8. In pure resistive AC circuit, 16. There are ___________ types of instantaneous value of voltage or modulations: current: a) 1 a) Current lags behind voltage b) 2 𝜋 b) Current leads voltage by 2 c) 3 c) Both are in-phase d) 4 𝜋 d) Voltage leads current by 2 1 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 16 17. The SI unit of impedance is: 25. If 𝑉𝑟𝑚𝑠 = 10 2 𝑣𝑜𝑙𝑡𝑠, then phase a) Henry voltage 𝑉0 will be: b) Hertz a) 10 𝑣𝑜𝑙𝑡𝑠 c) Ampere b) 20 𝑣𝑜𝑙𝑡𝑠 d) Ohm c) 40 𝑣𝑜𝑙𝑡𝑠 10 d) 2 𝑣𝑜𝑙𝑡𝑠 18. Which of the following is true for a step down transformer: a) 𝑁𝑃 > 𝑁𝑆 26. At resonance RLC series circuit shows b) 𝑁𝑃 < 𝑁𝑆 the behavior of: c) 𝑁𝑃 = 𝑁𝑆 a) Pure resistive circuit d) 𝑁𝑜𝑛𝑒 𝑜𝑓 𝑡ℎ𝑒𝑠𝑒 b) Pure capacitive circuit c) Pure inductive circuit 19. If 𝐼0 is the peak value of AC, its average d) Pure RLC circuit value over the complete cycle is: 𝐼 27. At resonance, the value of current in a) 02 RLC series circuit is equal to: 𝑉 b) 2𝐼0 a) 0 2 𝑅 c) 𝐼0 b) 𝑉0 𝑅 𝐼 d) 𝑧𝑒𝑟𝑜 c) 2 d) 𝑧𝑒𝑟𝑜 20. At resonance, the phase angle for RLC series resonance circuit equals: 28. At high frequency, RLC series circuit a) 0° shows the behavior of: b) 90° a) Pure inductive circuit c) 180° b) Pure resistive circuit d) 270° c) Pure capacitive circuit d) Pure RLC circuit 21. The unit of impedance is: a) 𝑂ℎ𝑚 29. The r.m.s. value of A.C current in b) 𝑂ℎ𝑚 −1 a) 0.707 Io c) 𝑂ℎ𝑚 − 𝑚 −1 b) 0.707 Vo d) 𝑛𝑜 𝑢𝑛𝑖𝑡 c) 0.707 Ro d) None 22. A device that allows permits flow of DC through the circuit easily, is called: 30. In pure resistive A.C. circuit the voltage a) Inductor and current are b) Capacitor a) In phase c) AC generator b) Voltage leads the current d) Transformer c) Current leads the voltage d) None 23. The phase difference between each pair of coils of a three phase AC generator 31. The waves which can also pass through is: the vacuum are a) 0° a) Matter wave b) 90° b) Mechanical wave c) 120° c) Electromagnetic wave d) 180° d) Transverse wave 24. Main reason for the world wide use of 32. The unit used for capacitive reactance is AC is that it can be transmitted to: a) Volt a) Short distances at very low cost b) Ampere b) Long distances at very high cost c) Joule c) Short distances at very high cost d) Ohm d) Long distances at very low cost 2 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 16 33. Power dissipated in pure inductor is: a) Large 42. In case of phasor diagram the vector b) Small rotates c) Infinite a) Clockwise d) Zero b) Anti clockwise c) Remain stationary 34. If the frequency of A.C in large the d) None reactance of capacitor is a) Large 43. The combine opposition of resistor, b) Small capacitor and inductor is called c) Zero a) Reactance d) None b) Resistor 35. In case of capacitor, the voltage lag c) Impedance behind the current by d) None a) 90o b) 60o 44. The S.I unit of impedance is called c) 30o a) Joule d) 180o b) Weber 36. In the pure inductor the resistance is c) Ampere d) Ohm a) Zero b) Maximum c) Minimum 45. When A.C. flow through RC series d) None circuit the magnitude of voltage is 2 2 a) 𝑉 = 𝐼 𝑅 + 𝑋𝐿 2 2 37. In pure inductive circuit the voltage b) 𝑉 = 𝐼 𝑅 + 𝑋𝐶 a) Lead the current by 90 o c) 𝑉 = 𝐼𝑅 b) Ledge the current by 90o d) None c) Remain same with current d) None 46. The magnitude of voltage in case of RL – series circuit 38. The reactance of inductor is represented 2 2 by a) 𝑉 = 𝐼 𝑅 + 𝑋𝐿 2 2 a) Xc b) 𝑉 = 𝐼 𝑅 + 𝑋𝐶 b) XL c) 𝑉 = 𝐼𝑅 c) RL d) None d) None 47. The average power in case of A.C. 39. If the frequency of A.C. is doubled, the series circuit is reactance of inductor will be a) 𝑃 = 𝑉𝐼 a) Half b) 𝑃 = 𝑉𝐼 cos c) 𝑃 = 𝑉𝐼 𝑠𝑖𝑛 b) Same c) Double d) None d) Triple 48. In equation P = VI cos , the factor cos 40. The average power dissipated in a pure inductor is is called a) Maximum a) Cosine factor b) Minimum b) Power factor c) Zero c) Phase d) None d) None 41. By increasing the frequency of A.C. 49. The behavior of resistance is frequency through an inductor the reactance will a) Dependent be b) Independent a) Increases c) No, response b) Decreases d) None of these c) Remain same d) None 3 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 16 50. The impedance Z can be expressed as: a) 𝑉𝑟𝑚𝑠 + 𝐼𝑟𝑚𝑠 59. The process of combing the low b) 𝑉𝑟𝑚𝑠 − 𝐼𝑟𝑚𝑠 frequency signal with high frequency 𝑉 radio-wave is called c) 𝑟𝑚𝑠 𝐼 𝑟𝑚𝑠 a) Modulation 𝐼𝑟𝑚𝑠 b) Amplification d) 𝑉𝑟𝑚𝑠 c) Rectification 51. At resonance frequency the power factor d) None is a) One 60. A capacitor is perfect insulator for: b) Zero a) Alternating current c) Two b) Direct current d) Three c) Both a and b d) None 52. The frequency at which XL is equal to XC in called 61. During each cycle A.C voltage reaches a) Resonance frequency its peak value b) Threshold frequency a) One time c) Non-frequency b) Two times d) None c) Four times d) None of these 53. At resonance frequency the impedance of A.C series circuit is 62. In modulation, high frequency radio a) Maximum wave is called: b) Minimum a) Fluctuated wave c) Can not explain by give data b) Carrier wave d) None c) Matter wave d) Energetic wave 54. In parallel RLC circuit , at resonance frequency, there will be maximum 63. At high frequency the reactance of the a) Power capacitor is b) Voltage a) Low c) Impedance b) Large d) None c) Very large d) None of these 55. The electrical oscillators are used in a) Metal detectors 64. The behavior of resistance is frequency b) Amplifier a) Dependent c) Diode b) Independent d) None c) No response d) None of these 56. Which of the following permits direct current to flow easily? 65. In an inductor the phase difference a) Resistance between the current and voltage is b) Capacitance a) Current lags voltage by 90o c) Inductance b) Voltage lags current by 180o d) None of these c) Current leads voltage by 90o d) None of these 57. A.M stands for a) Amplitude Modulation 66. The condition of resonance reached b) Applied Metal when c) Accurate Measurement a) XC > XL d) None b) XL < XC c) XL = XC 58. F.M stands for d) None of these a) Frequency Modulation b) Frequency Metal c) Frequency Member d) None 4 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 16 67. The phase difference between coils of 69. How many times per second will an three phase A.C is incandescent lamp reach maximum a) 60o brilliance when connected to a 50Hz b) 45o source? c) 90o a) 50 times d) 120o b) 100 times c) 200 times 68. Modulation is the process in which d) None of these a) Amplitude is change b) Frequency is change 70. The peak value of sinusoidal voltage in c) Both a & b an AC circuit is 50V. The rms value of d) None of these voltage is roughly equal to a) 70V b) 40V c) 35V d) 45V 71. In RLC series AC circuit, when XL = XC then impedance is a) Minimum b) Maximum c) Zero d) None 5 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 17 CHAPTER # 17. PHYSICS OF SOLIDS 8. Substances which break just after the elastic 1. What is the S.I unit of modules of elasticity of limit is reached are called: substances? a) Ductile substances a) Nm-2 b) Hard substances b) Jm-2 c) Soft substances c) Nm-1 d) Brittle substances d) Being number, it has no unit 9. Cure temperature for iron is: 2. The bands in atom containing conductive a) 0 ℃ electrons, according to “band theory of solids” b) 570 ℃ is c) 750 ℃ a) Conduction band d) 1025 ℃ b) Valance band c) Forbidden band 10. The SI unit of stress is same as that of: d) None of these a) Momentum b) Pressure 3. The substances which have partially filled c) Force conduction bands are called: d) Length a) Insulators b) Semi-conductors 11. Which of the following has least energy gap? c) Conductors a) Conductors d) Super conductors b) Insulators c) Semi-conductors 4. What type of impurity is to be added to the d) None of these semi-condutor material to provide holes: a) Monovalent 12. A magnetism produced by electrons within an b) Trivalent atom is due to: c) Tetravalent a) Spin motion of electrons d) Pentavalent b) Orbital motion of electrons c) Both Spin and orbital motion of electrons 5. Which of the following is an example of d) Vibratory motion of electrons ductile substances: a) Lead 13. If the conductivity of a material is high, then it b) Copper is: c) Glass a) An insulator d) Lead and copper b) A semi-conductor c) A good conductor 6. When a stress changes the shape of a body, it d) A super condutor is called: a) Volumetric stress 14. A substance having empty conduction band is b) Shear stress called: c) Tensile stress a) Semi-conductor d) Compressional strees b) Conductor c) Insulator 7. The ration of applied stress to volumetric d) None of these strain is called: a) Young’s modulus 15. The stress that produces change in length is b) Shear modulus known as: c) Bulk modulus a) Tensile stress d) Tensile modulus b) Shear stress c) Volumetic stress d) Longitudenal stress 1 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 17 16. What are the dimensions of stress? a) MLT-2 24. The energy band occupied by the valence b) ML-2T-1 electrons is called ________ c) ML-1T-2 a) Energy state d) MLoT-1 b) Valence band c) –ve energy state 17. Which one of the following physical quantities d) Conduction band does not have the dimensions of force per unit? 25. the substances having negative temperature a) Stress coefficient of resistance is called: b) Strains a) Conductors c) Young’s modulus b) Insulators d) Pressure c) Semi-conductor d) None of these 18. Germanium is: a) semi-conductor 26. The Curie temperature is that at which ______ b) conductor a) Semi conductor becomes conductors c) insulator b) Ferromagnetic becomes paramagnetic d) none of these c) Paramagnetic becomes diamagnetic d) Metal becomes super conductor 19. unit of strain is: 𝑁 27. Materials in which valence electrons are a) 𝑚 2 𝑁 tightly bound to their atoms at low temperature b) 𝑚 are called _________ c) 𝑁 𝑚 a) Semi conductors d) 𝑛𝑜 𝑢𝑛𝑖𝑡 b) Super conductors c) Insulators 20. At curie temperature, iron becomes: d) Conductors a) Ferromagnet b) Diamagnet 28. The band theory of solids explains c) Paramagnet satisfactorily the nature of d) Super-conductor a) Electrical insulators alone 21. Materials that undergo plastic deformation b) Electrical conductors alone before breaking are called ___________ c) Electrical semi conductors alone a) Brittle d) All of the above b) Ductile c) Amorphous 29. A vacant or partially filled band is called d) Polymers _____ a) Conduction band 22. Formation of large molecule by joining b) Valence band small molecules is __________ c) Forbidden band a) Fusion d) Empty band b) Polymerization c) Crystallization 30. A completely filled or partially filled band is d) Subtraction called _______ a) Conduction band 23. Any alteration produced in shapes, length or b) Valence band volume when a body is subjected to some c) Forbidden band external force is called __________ d) Core band a) Stiffness b) Ductility c) extension d) deformation 2 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 17 31. Which one has the greatest energy gap 39. The temperature at which conductors lose its _______ resistivity is called a) Semi-conductors a) Supper temperature b) Conductors b) Kelvin temperature c) Metals c) Critical temperature d) Non-metals d) None 32. With increase in temperature, the 40. The magnetic domains are the small regions of electrical conductivity of intrinsic semi conductors the order of ______ a) Millimeter a) Decreases b) Micrometer b) Increases c) Micron c) Remain the same d) None of these d) First increases, then decreases 41. N-type semi-conductor is obtained by doping 33. Holes can exists in_________ intrinsic semi-conductors with ___________ a) Conductors a) Tetravalent impurity atom b) Insulators b) Trivalent impurity atom c) Semi conductors c) Pentavalent impurity atom d) All of the above d) Hexavalent impurity atom 34. In a semi conductors, the charge carriers 42. The first supper conductor was discovered by are __________ a) Fermi a) Holes only b) Kmaerling b) Electrons only c) Weinberg c) Electrons and holes both d) None d) All of the above 43. Examples of brittle substances are 35. The net charge on N-type material is a) Glass ________ b) Copper a) Positive c) Lead b) Negative d) None c) Both a & b d) Neutral 44. Example of crystalline solids are also a) Metals 36. The most stable material for making b) Ionic compounds permanent magnet is: c) Ceramics a) Iron d) All of them b) Steel c) Aluminum 45. a semi-conductor will behave as insulator d) Copper when: a) High potential difference is applied 37. Pentavalent impurities are called b) When its temperature is 0 k a) Donor impurities c) Pentavalent impurity added b) Acceptor impurities d) Trivalent impurity added c) Sometimes donor and some times d) Acceptors 46. The field of long bar magnet is like a a) Solenoid 38. Minority carriers in N-type materials are b) Toroid a) Electrons c) Pieces of magnet b) Protons d) None c) Neutrons d) Holes 3 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 17 47. The curie temperature of Iron is a) 600oC 55. A current which demagnetize the material b) 650oC completely is called c) 700oC a) Applied current d) 750oC b) Coercive current c) Maximum current 48. The examples of diamagnetic are d) None of these a) Water b) Copper 56. The energy need to magnetize and c) Antimony demagnetize the specimen during the each d) All of them cycle of magnetizing current is a) Value of current 49. Strain is dimensionless and has b) Value of demagnetizing current a) Units c) Value of magnetic flux density b) No units d) Area of the loop c) S.I units d) None 57. The temperature below which resistivity of some materials becomes zero, is called: 50. The electrons occupying the outermost shell of a) Kelvin temperature an atom and the electrons occupying in the b) Critical temperature energy band are called c) Absolute zero temperature a) Energy band d) Limiting temperature b) Valence band c) Forbidden energy band 58. A well known example of an intrinsic semi- d) None of these conductor is: a) Germanium 51. Conductors are those materials in which the b) Phosphorous free electrons c) Aluminum a) Very large d) Cobalt b) Very small c) Plenty of 59. The critical temperature for mercury is: d) None of these a) 7.2 K b) 4.2 K 52. The magnetism produced by electrons within c) 1.18 K an atom is due to d) 3.7 K a) Spin motion 60. Holes can exist in: b) Orbital motion a) Super conductors c) Spin & orbital motion b) Conductors d) None of these c) Semi-conductors d) Insulators 53. The combination of solenoid and a specimen of iron inside it make a powerful magnet called a) Horse shoe magnet b) Bar magnet c) Electromagnet d) None of these 54. the substance in which the atoms don’t form magnetic dipole are called: a) ferromagnetic b) paramagnetic c) diamagnetic d) conductors 4 www.educatedzone.com F Sc (2nd year) Physics MCQ’s Chapter # 18 CHAPTER # 18. ELECTRONICS 8. A diode characteristics curve is a graph plotted 1. A semi – conductor can be used as a rectifier between because a) Current and time a) It has low resistance to the current flow b) Voltage and time when forward biased c) Voltage and current b) It has high resistance to the current flow d) Forward voltage and reverse current when reversed biased 9. The output of AND gate will be 1 when c) It has low resistance to the current flow when forward biased and high resistance a) Both inputs are at 0 b) Either one input is at 1 when reversed biased d) None of the above c) Both inputs are at 1 d) None of these 2. The central region of a transistor is called: 10. For non-inverting amplifiers if 𝑅1 = ∞ Ω and a) Base 𝑅2 = 0 Ω, then gain of amplifier is b) Emitter a) -1 c) Collector b) 0 d) Neutral c) +1 d) infinite 3. The SI unit of current gain is: a) Ampere 11. An expression for current gain of a transistor is b) Volt given by 𝐼 c) Ohm-meter a) 𝛽 = 𝐵 𝐼𝐶 d) It has no units b) 𝛽 = 𝐼𝐵 + 𝐼𝐶 4. A NAND gate with two inputs A & B has an c) 𝛽 = 𝐼𝐶 − 𝐼𝐵 𝐼 output 0 if d) 𝛽 = 𝐼𝐶 𝐵 a) A is 0 b) B is 0 12. In n-type materials, the minority carriers are c) Both A and B are 0 a) Free electrons d) Both A and B are 1 b) Holes c) Protons 5. The gain G of non inverting operational d) Mesons amplifier is 𝑅 13. Transistors are made from a) 𝐺 = − 𝑅2 1 a) Plastics 𝑅 b) 𝐺 = 1 + 𝑅2 b) Metals 1 𝑅2 c) Insulators c) 𝐺 = d) Doped semi-conductors