Q,I Objective Question (a) I. 2. 3. 4. 5. 6. 7. Answer the following mulliple choice questions. Which of the following relations is incorrect? (a) P=V 2G (b) V= -IPR (c) G=P/12 (d) J=✓(P/R) P= power. Y= Yollage, I= current, R=resistance. G=conductance Ohm's law is not applicable to (a) ac circuit (b) de circuit (c) semi-conductor (d) linear circuits Which of the following is a vector quantity? (a) electric charge (b) electrical potential (c) electric field intensity (d) none of the above Which law states that the induc.ed e.m.f. and current always oppose the cause of producing them? (a) Lenz (b) A eming (c) Faraday (d) Maxwell Which of the following frequencies has the longest tjme period? (a) 10 kHz (b) I kHz (c) 10 Hz (d) I Hz The resonance frequency for the series RLC circuit where. R= I 00 0, L = 80 mH. C = 3 i60 pF. (a) 15 kH z (b) 10 kHz (c) 8 kHz (d) 12 kHz Series connection of cells (b) increa<,es the voltage output (a) increases the efficiency (c) increases the current output (d) decreases the int.emal resistance Mark 07 Q.1 (a) I. 2. 3. 4. 5. 6. 7. Objective Question (MCQ) Choose the most appropriate option from the following. The nodal method of circuit analysis is based on _ _ _ __ (a) KCL and Ohm's law (b) KVL and Ohm's law (c) KCL and KVL (d) KCL KVL and Ohm's law In which of the follo wing types of capacitors. care s hould be taken with regard to the polarity while connecting it in a circuit? (u) Paper capacitor (b) Cer.unic capacitor (c) Electrolytic capacitor (d) Mica capacitor Permeance is analogous to _ _ __ (a) resistivity (b ) reluctance (c) resistance (d) conductance A current is said to be alternating when it changes in _ _ _ _ __ (a) magnitude only (b) direction only (c) both magnitude and direction (d) neither magnitude nor direction In a series RLC high Q circuit. the current peaks at a frequency _ _ __ (a) greater than the resonant frequency (b) equal to the resonant frequency (c) les.11 than the resonant frequency (d) none of the these The rated voltage of a three-phase power system is given as _ _ __ (a) rrns phase voltage (b) rrns line to line voltage (c) peak pha,;e voltage (d) peak line to line voltage The major advantage of secondary cell is that _ _ _ __ (a) electrolyte used is very cheap (b) chem.ical action not reversible (c) chemical action is reversible (d) none of the these 07 Q.1 Mark Objective Question (MCQ) (a) 07 1. A d.c Circuit usually has ...................as the load (a)inductance (b) resistance (c) capacitance 1. There are 1wo charges of +lµC and +5µC.The ratio of lhe forces acting on lhem will be (a)l:I (b)l:5(c)5: I (d) l :25 3. A parallel plale air capacilor has a capacitance C. if air between 1he plates is exhausted completely, 1he new capacitance would become (a)2.ero (b)C (c)Sligh1ly more 1han C (d)Slightl y less 1han C 4. Mag netic lines of the force (a) Intersect at infinity (b) Intersect within lhe magnet com (c) Cannot intersect al all (d) None of the above S. The unit of pole strength is ................ .. (a)A/m 2 (b)Am (c) Am2 (d)Wb/m2 6. The fluorescent tube is filled wilh low pressure .... .. ... ... .. . gas and drop of (a)argon, phosphorus (b)helium. mercury(c)argon. mercury 7. In HRC fuse, the fusing element is . .... .. . .. .... . (a)cupper (b)Aluminum {c)SiJver (d)Gold Q.1 (a) I. 2. Choose the mo.fl appropriate option. 07 lf temperature of m.etal is increased. temper.iture coefficient of resistance wilJ __ (a) increase (b) decrease (c) remain unaffected (d) become zero What is equivalent resistance between A B points A and B in fig. I ? R is in n. (a) 3R (b) - I 3R R (c) - (d) zero R 3 Fig. I 3. Aux linkage per unit c urrent is defined as _ __ 4. (a) reluctance (b) inductance (c) permeance (d) magnetomotive force lf a network has an impedance ofz • IO L - 10 · n, which of the following S. 6. 7. statements is correct? (a) current lags behind voltage by I o· (b) current lead:s ahead voltage by I o· (c) currenl is in phase with voltage (d) current is in phase opposition with voltage Power consumption over a cycle in purely inductive circuit __ (a) depends on L (b) depends on supply voltage (c) zero (d) infinity Halogen lamp is a type of _ __ (a) CFL (b) discharge lamp (c) incandescent lamp (d) LED lamp The resistance of human body is about _ _ (a) 1 n (b) 10 o (c) 100 n (d) 1000 n Q.1 Objective Questions. 07 (a) I. The unit of current is_ _ _ _ _ _ __ (a) Vol!/sec (b) coulo:mb/sec (c) ;unp/sec (d) none of Olese 2. J. 4. Coulomb's second law is called as _ _ _ _ _ _ _ law. (a) Inverse square (b) charge (c) induction If the length of conductor is doubled and its cross sectional area is reduced to 500/o then its resistance will be._ _ _ _ __ (a) Same (b) doubled (c) increased by 4 times (d) reduced to I/4th A conductor carries IOA in a direction perpendicular to a magnetk field of density 0.3T. If the length of conductor is 10 cm the force on the conductor F= (a) 3 N (b) 0.3 N (c) 30 N Amount of light produced by a lump or the amount of heat produced by an iron is proportional to the _ _ _ _ __ - -- - -- - S. (a) Square of RMS value (b) RMS value (c) square of average value 6. 7. Mark (d) average value. The three phase voltages are displaced by _ _ _ _ _ radians from each other. (a) rr/2 (b) rr/3 (c) 2rr/3 (d) x Define Lumens. Q.1 Objective Question - select only one option out of four (MCQ) 07 (a) 1. 2. 3. 4. 5. 6. 7. (b) 1. 2. 3. 4. s. 6. 7. MARKS Which of the following material has nearly zero temperature co-efficient of resistance ? [aj Carbon [bl copper lcJ porcelain [d] manganin The unit of absolute permittivity of a medium is [di joule/coulomb [a] farad/coulomb [b] newton-m [c] farad/m The unit of resistivity is [a) Ohm/ m lb) Ohm-m [c] mho/m Id) mho-m Time constant of an R-C ckt. may be defined as (a] Lime during which capacitor voltage rises to 0.632 of its initial value [b] time during which charging current fall s to 0 .37 of its initial max. value [c] time during which capacitor voltage falls to 0 .632 of its final steady value [d] time during which charging current rises to 0.37 of its initial max. value The unit of reluctance is [a] AT/ Wb fb] Wb / AT (c] I/Henry [d] either fbl or [c] Wh efficiency of lead-acid cell is _ _ _ _ Ah efficiency. [a] greater than [b] smaller than [c] equal to [d] none of this The value of form factor is [a] I I. I [b] 1.11 [c] 1.414 [d] 14.14 07 The value of power factor is zero for [a] purely inductive ckt. fb] purely resistive ckt. [c] purely capacitive ckt. [d] either [a] or [c] For a series resonance condition of AC circuit impedance is [a] minimum [b] maximum [c] zero [d] infinity The filament used in incandescent lamp is made of [a] copper fb) alluminium [c] nichrome [d] tongston The value of crest factor is [a) I I.I [b] I.I I [c] 1.414 [d) 14.14 For a parallel resonance condition of a AC circuit current is [a] minimum [b] maximum [c] zero [d] infinity For unity power factor load of 3-phase ckt.,if we measure the power by 2wattmeter method then readings of wattmeters are [a] one watlmeter shows zero reading [b] equal & +ve sign [c] equal & opposite sign fd] both shows zero reading The power factor of R-C series Ac ckt. is (a] unity [b] lagging [c] leading [d] zero Q.1 Objective Question (MCQ) 07 (a) 1. Fiber optic cable is used for_ _ _ __ a) Point to point tr.msmission b) High power transmission c) High voltage transmission d) High current transmission 2. A test lamp is used for _ __ a) Presence of voltage b) Testing earthing c) Measurement of resistance d) Measurement of voltage. 3. ____is not an ekctrical element. a) Tester b) Resistor c) lnductor d) Capacitor 4. Approximaic life of incandescent lamp is _ _ _ hours. a) 100 b) 1000c) 10000d) 100000 5. Megger is used for ____ measurement. a) Insulation resistance b) low resistance c) medium resistance d) current 6. 6. The process of connecting metallic body part of alJ electrical apparatus to earth is known as _ _ __ a) Piping b) wiring c) earthing d) insulating. 7. Mercury vapour lamp is a r.ype of _ _ _ _ lamp. a) Incandescent b) Resistance c) High intensity discharge d) High current discharge.