87 + Interview Questions in Electromagnetism in Basic Electrical Engineering Page 1 InterviewSolution

1.	What is the consequence of motor effect?(a) Current(b) Voltage(c) Electromagnetic induction(d) EMFI had been asked this question during an internship interview.The origin of the question is Electromagnetic Induction topic in division Electromagnetism of Basic Electrical Engineering
Answer» Right choice is (c) ELECTROMAGNETIC induction The BEST I can explain: Motor EFFECT is when a current carrying conductor in a magnetic field experiences a force, HENCE its CONSEQUENCE is electromagnetic induction.

Discussion

2.	Force in a conductor is__________ to the product of the charges.(a) Directly proportional(b) Inversely proportional(c) Not related(d) Cannot be determinedThis question was addressed to me in final exam.This question is from Force on a Current Carrying Conductor topic in chapter Electromagnetism of Basic Electrical Engineering
Answer» The correct choice is (a) Directly proportional Best explanation: The force in a current carrying CONDUCTOR is directly proportional to the PRODUCT of the two charges and INVERSELY proportional to the SQUARE of the DISTANCE between them.

Discussion

3.	Which, among the following qualities, is not affected by the magnetic field?(a) Moving charge(b) Change in magnetic flux(c) Current flowing in a conductor(d) Stationary chargeI have been asked this question at a job interview.Asked question is from Magnetic Field topic in chapter Electromagnetism of Basic Electrical Engineering
Answer» The CORRECT answer is (d) Stationary charge To EXPLAIN: A stationary charge is not affected by a MAGNETIC field because stationary charges do not have any velocity. Magnetic field cannot occur in a PARTICLE having zero velocity.

Discussion

4.	“The direction of an induced e.m.f. is always such that it tends to set up a current opposing the motion or the change of flux responsible for inducing that e.m.f.”, this is the statement for?(a) Fleming’s left hand rule(b) Fleming’s right hand rule(c) Faraday’s law(d) Lenz’s lawI have been asked this question in examination.My query is from Direction of Induced EMF in portion Electromagnetism of Basic Electrical Engineering
Answer» CORRECT OPTION is (d) LENZ’s law Explanation: The above statement is that of Lenz’s law. It is used to determine the DIRECTION of the induced EMF.

Discussion

5.	North pole induces __________(a) Clockwise current(b) Anti-clockwise current(c) Zero current(d) Infinite currentI have been asked this question in a national level competition.Asked question is from Magnitude of the Generated or Induced EMF topic in division Electromagnetism of Basic Electrical Engineering
Answer» The correct choice is (b) Anti-clockwise current To EXPLAIN: A NORTH pole will always induce an anti-clockwise current WHEREAS a south pole will always induce a clockwise current DUE to electromagnetic theory.

Discussion

6.	Find the strength of the magnetic field in a conductor 0.5m long moving with a velocity of 10m/s, inducing an emf of 20V if magnetic field, velocity and length of conductor are mutually perpendicular to each other.(a) 1T(b) 2T(c) 3T(d) 4TI got this question in an interview.I want to ask this question from Electromagnetic Induction topic in portion Electromagnetism of Basic Electrical Engineering
Answer» Right OPTION is (d) 4T Easiest explanation: The formula for induced EMF is: emf=Blv if B, l, V are perpendicular to each other. Substituting the values of l, emf and v from the QUESTION, we get B=4T.

Discussion

7.	Which among the following, is the correct expression for force in a current carrying conductor if magnetic field is perpendicular to it?(a) F=Bi(b) F=B^2il(c) F=Bil(d) F=Bl^2I had been asked this question in final exam.The above asked question is from Force Determination in portion Electromagnetism of Basic Electrical Engineering
Answer» CORRECT CHOICE is (c) F=Bil To elaborate: The correct expression for force in a CURRENT carrying conductor in a MAGNETIC FIELD perpendicular to it is F=Bil, where B is the magnetic field, i is the current in the conductor and l is the length of the conductor.

Discussion

8.	The current in a solenoid is 30A, the number of turns per unit length is 500 turns per metre. Calculate the magnetic field if the core is air.(a) 18.84T(b) 18.84mT(c) 1.84T(d) 1.84mTThe question was asked in an internship interview.This intriguing question originated from Magnetic Field of a Solenoid in chapter Electromagnetism of Basic Electrical Engineering
Answer» The correct option is (b) 18.84mT The best EXPLANATION: The MAGNETIC field in a solenoid is given by: B=μnI Substituting the VALUES in the given values in the equation, B=18.84mT.

Discussion

9.	The force existing between two infinite parallel conductors is inversely proportional to ________(a) Radius of the conductors(b) Current in one of the conductors(c) The product of the current in the two conductors(d) The distance between the two conductorsThis question was posed to me at a job interview.The doubt is from Magnetic Field Due to an Electric Current in chapter Electromagnetism of Basic Electrical Engineering
Answer» Correct choice is (d) The distance between the two CONDUCTORS The explanation: When current is flowing in two DIFFERENT conductors, the force between the two conductors is directly PROPORTIONAL to the PRODUCT of the current in the two conductors and INVERSELY proportional to the distance between the two conductors.

Discussion

10.	According to Flemming’s left hand rule, the thumb denotes?(a) Direction of magnetic field(b) Direction of current(c) Direction of force(d) Direction of force as well as currentI got this question in my homework.This interesting question is from Direction of Magnetic Field topic in division Electromagnetism of Basic Electrical Engineering
Answer» The correct option is (C) Direction of force Best explanation: According to Flemming’s left HAND rule, the index finger denotes the direction of the magnetic field, the THUMB DENOTED the direction of force and the middle finger denoted the direction of the CURRENT.

Discussion

11.	Field lines move from __________(a) North to south(b) South to north(c) West to east(d) East to westThis question was posed to me in exam.This intriguing question originated from Direction of Magnetic Field topic in section Electromagnetism of Basic Electrical Engineering
Answer» The correct answer is (a) NORTH to south Explanation: Magnetic field LINES originate at the north pole and TERMINATE at the south pole of the MAGNET.

Discussion

12.	Can we see magnetic flux lines?(a) Yes(b) No(c) Depends on the strength of the field(d) Only when the field strength is very largeThe question was asked during an online interview.Query is from Magnetic Field topic in division Electromagnetism of Basic Electrical Engineering
Answer» The CORRECT choice is (b) No For explanation I WOULD SAY: No, we cannot SEE magnetic flux lines as the “lines of magnetic flux” is purely an imaginary concept to UNDERSTAND the magnetic field clearly.

Discussion

13.	How can a magnetic field be produced?(a) Using a permanent magnet(b) Electric current(c) Using a temporary magnet(d) Using a permanent magnet or electric currentThe question was asked in exam.The above asked question is from Magnetic Field in division Electromagnetism of Basic Electrical Engineering
Answer» RIGHT option is (d) Using a permanent MAGNET or electric CURRENT Explanation: An electric current as well as the permanent magnet produces a magnetic field WHEREAS a TEMPORARY magnet fails to do so.

Discussion

14.	Find the length of a conductor which is moving with a velocity 0.4m/s in a magnetic field of 8T, inducing an emf of 20V if magnetic field, velocity and length of conductor are mutually perpendicular to each other.(a) 50m(b) 5m(c) 6.25m(d) 0.5mI had been asked this question in examination.I need to ask this question from Electromagnetic Induction topic in chapter Electromagnetism of Basic Electrical Engineering
Answer» The correct answer is (c) 6.25m The best I can explain: The formula for INDUCED EMF is: emf=Blv if B, l, v are PERPENDICULAR to each other. SUBSTITUTING the values of B, emf and v from the question, we get l=6.25m.

Discussion

15.	According to Fleming’s right hand rule, the index finger points towards?(a) Current(b) E.M.F.(c) Motion of the conductor(d) Magnetic fluxThis question was addressed to me in an interview for job.My query is from Direction of Induced EMF topic in section Electromagnetism of Basic Electrical Engineering
Answer» Correct answer is (d) Magnetic flux Best explanation: FLEMING’s left hand RULE stated that if the index finger points towards magnetic flux, the THUMB towards the motion of the CONDUCTOR, then the middle finger points towards the induced EMF.

Discussion

16.	What happens to the current in a coil while accelerating a magnet inside it?(a) Increases(b) Decreases(c) Remains constant(d) ReversesThis question was addressed to me in final exam.The question is from Electromagnetic Induction in portion Electromagnetism of Basic Electrical Engineering
Answer» Correct answer is (a) INCREASES For explanation I would say: A change in the MAGNETIC FIELD INDUCES an emf. When there is an emf, there has to be current. Hence, when the magnet is moved inside a COIL, the current in it increases.

Discussion

17.	If the intensity of the magnetic field is 100T, the length of the conductor is 10m and the magnitude of force perpendicular to the magnetic field is 10kN,calculate the current in the conductor.(a) 100 A(b) 100 mA(c) 10 A(d) 10 mAThis question was posed to me in class test.Asked question is from Force Determination topic in chapter Electromagnetism of Basic Electrical Engineering
Answer» The correct choice is (c) 10 A The explanation: The formula for calculating the VALUE of the FORCE which is PERPENDICULAR to the magnetic FIELD is: F=Bil Substituting the values from the question, we get i = 10A.

Discussion

18.	The relation between the direction of force and the direction of magnetic field is __________(a) Same direction(b) Opposite direction(c) Perpendicular(d) UnrelatedThis question was addressed to me in class test.My question comes from Force on a Current Carrying Conductor topic in portion Electromagnetism of Basic Electrical Engineering
Answer» The correct CHOICE is (C) Perpendicular For explanation: When a CONDUCTOR carries a certain value of current, the force DEVELOPED in the conductor, the current in the conductor and the magnetic FIELD in the conductor are mutually perpendicular to each other.

Discussion

19.	When the magnetic field intensity in the current carrying conductor increases, what happens to the force in the conductor which is at right angles to the magnetic field?(a) Increases(b) Decreases(c) Remains the same(d) Becomes zeroThis question was addressed to me at a job interview.My doubt is from Force Determination in portion Electromagnetism of Basic Electrical Engineering
Answer» Right OPTION is (a) Increases Explanation: The force at right angles to the magnetic field of a CURRENT carrying CONDUCTOR increases when the magnetic field intensity increases because it is directly proportional to the force.

Discussion

20.	The ratio of magnetic force to electric force on a charged particle getting undeflected in a field is ______(a) 1(b) 0(c) 2(d) 4I have been asked this question during an online exam.This intriguing question originated from Force on a Current Carrying Conductor in portion Electromagnetism of Basic Electrical Engineering
Answer» Right OPTION is (a) 1 Explanation: When a CHARGED particle is undeflected in a field, the magnitude of the magnetic FORCE and electric force acting on the particle is the same, hence the ratio is 1.

Discussion

21.	Magnetic field lines seek the path of __________ resistance.(a) Maximum(b) Minimum(c) Infinite(d) ZeroI had been asked this question in final exam.My question is based upon Characteristics of Lines of Magnetic Flux topic in chapter Electromagnetism of Basic Electrical Engineering
Answer» RIGHT option is (b) Minimum For explanation: Magnetic FIELD LINES will always seek the path of least resistance. It does not seek the path of zero resistance because, in practical scenarios, zero resistance is not POSSIBLE.

Discussion

22.	The relation between the direction of force and the direction of magnetic field is _________(a) Same direction(b) Opposite direction(c) Perpendicular(d) UnrelatedI got this question in an online quiz.This interesting question is from Direction of Magnetic Field in division Electromagnetism of Basic Electrical Engineering
Answer» Right choice is (c) Perpendicular Easy EXPLANATION: When a conductor carries a CERTAIN VALUE of current, the force DEVELOPED in the conductor, the current in the conductor and the magnetic FIELD in the conductor are mutually perpendicular to each other.

Discussion

23.	What is the strength of magnetic field known as ________(a) Flux(b) Density(c) Magnetic strength(d) Magnetic flux densityI got this question in an interview for internship.I would like to ask this question from Magnetic Field topic in division Electromagnetism of Basic Electrical Engineering
Answer» RIGHT answer is (d) Magnetic flux density The EXPLANATION is: STRENGTH of magnetic FIELD is ALSO known as magnetic flux density. It is the amount of magnetic field lines crossing unit area.

Discussion

24.	If a conductor 0.2m long moves with a velocity of 0.3m/s in a magnetic field of 5T, calculate the emf induced if magnetic field, velocity and length of conductor are mutually perpendicular to each other.(a) 0.3V(b) 0.03V(c) 30V(d) 3VThis question was addressed to me in semester exam.My doubt is from Electromagnetic Induction in division Electromagnetism of Basic Electrical Engineering
Answer» Correct option is (a) 0.3V To explain: The formula for INDUCED emf is: emf=Blv if B,L,v are PERPENDICULAR to each other. Substituting the VALUES of B, l and v from the question, we get emf=0.3V.

Discussion

25.	The formula for induced emf if magnetic field, length and velocity of conductor all are mutually perpendicular is __________(a) emf=B^2l(b) emf=Bil(c) emf=Blv(d) emf=B^2vThe question was asked during an online interview.My question is based upon Electromagnetic Induction in portion Electromagnetism of Basic Electrical Engineering
Answer» The correct choice is (C) emf=Blv Explanation: The formula for induced emf is emf=Blv, where B is the magnetic field, L is the length of the CONDUCTOR and v is the velocity with which it is moving in the magnetic field and all three quantities are mutually perpendicular to each other.

Discussion

26.	The magnetic field of the solenoid is 18.84mT, the current is 30A. Calculate the number of turns per unit length if the core is air.(a) 1500 turns/m(b) 1000 turns/m(c) 500 turns /m(d) 2000 turns/mI had been asked this question in semester exam.The doubt is from Magnetic Field of a Solenoid in division Electromagnetism of Basic Electrical Engineering
Answer» Correct CHOICE is (C) 500 turns /m To explain: The MAGNETIC field in a SOLENOID is given by: B=μnI Substituting the values in the given values in the EQUATION n=500 turns/m.

Discussion

27.	Calculate the force between two charges having magnitude 3nC and 2nC separated by a distance of 2micro m.(a) 13.5N(b) 13.5kN(c) 1.35N(d) 1.35kNThis question was addressed to me during an interview for a job.I'd like to ask this question from Force on a Current Carrying Conductor in chapter Electromagnetism of Basic Electrical Engineering
Answer» The CORRECT ANSWER is (B) 13.5kN Explanation: From the EXPRESSION: F=Kq1q2/r^2, the value of K being 9*10^9, we get F=13.5kN.

Discussion

28.	What happens to the magnetic field in the solenoid when the current increases?(a) Increases(b) Decreases(c) Remains constant(d) Becomes zeroThis question was posed to me in class test.This key question is from Magnetic Field of a Solenoid topic in section Electromagnetism of Basic Electrical Engineering
Answer» Right CHOICE is (a) Increases Explanation: The magnetic FIELD of a SOLENOID is directly proportional to the current in it. Hence as the current increases, the magnetic field ALSO increases.

Discussion

29.	More the number of magnetic flux lines _______ is the force of the magnet.(a) Greater(b) Lesser(c) Either greater or lesser(d) Neither greater nor lesserThis question was addressed to me in examination.My query is from Characteristics of Lines of Magnetic Flux topic in chapter Electromagnetism of Basic Electrical Engineering
Answer» Correct ANSWER is (a) Greater For explanation: More the number of magnetic flux lines, greater is the force of the magnet. This is because the magnetic flux lines DENOTE the strength of the FIELD of the magnet.

Discussion

30.	According to Flemming’s left hand rule, the index finger denotes?(a) Direction of magnetic field(b) Direction of current(c) Direction of force(d) Direction of force as well as currentThis question was addressed to me during an online interview.The doubt is from Direction of Magnetic Field topic in division Electromagnetism of Basic Electrical Engineering
Answer» Right CHOICE is (a) Direction of magnetic field To EXPLAIN I would say: ACCORDING to Flemming’s LEFT hand rule, the index finger denotes the direction of the magnetic field, the thumb denoted the direction of force and the MIDDLE finger denoted the direction of the current.

Discussion

31.	Magnetic field lines ___________ at the north pole.(a) Emerge(b) Converge(c) Neither emerge nor converge(d) Either emerge or convergeThe question was posed to me in an interview.My question is from Direction of Magnetic Field in section Electromagnetism of Basic Electrical Engineering
Answer» The CORRECT answer is (a) Emerge Explanation: Magnetic FIELD lines emerge at the north pole. Field lines SEEM to emerge at the north pole because they ORIGINATE at the north pole.

Discussion

32.	Which of the following is used to determine the direction of magnetic field in a current carrying conductor?(a) Left hand thumb rule(b) Right hand thumb rule(c) Right hand palm rule(d) Left hand palm ruleThis question was posed to me in class test.My enquiry is from Direction of Magnetic Field in division Electromagnetism of Basic Electrical Engineering
Answer» The correct choice is (b) Right HAND thumb rule Easy explanation: The right hand thumb rule determines the direction of a magnetic FIELD in a CURRENT carrying CONDUCTOR. The rule STATES that when we align our right thumb in the direction of the current and curl our fingers around it, the direction of our fingers is the direction of the magnetic field.

Discussion

33.	What is the expression for force in a current carrying conductor?(a) F=K/r^2(b) F=Kq/r^2(c) F=Kq1q2/r^2(d) F=Kq1q2/rI had been asked this question during an interview for a job.The question is from Force on a Current Carrying Conductor topic in section Electromagnetism of Basic Electrical Engineering
Answer» Right option is (c) F=Kq1q2/r^2 The best explanation: The force in a current carrying conductor is directly PROPORTIONAL to the product of the two CHARGES and inversely proportional to the square of the distance between them. HENCE F=Kq1q2/r^2, where K is the constant of PROPORTIONALITY.

Discussion

34.	What happens to the magnetic field in the solenoid when the length of the solenoid increases?(a) Increases(b) Decreases(c) Remains constant(d) Becomes zeroThe question was asked in exam.Question is taken from Magnetic Field of a Solenoid in section Electromagnetism of Basic Electrical Engineering
Answer» The CORRECT ANSWER is (b) Decreases To explain: The magnetic FIELD of a solenoid is inversely proportional to the length. HENCE as the length increases, the magnetic field decreases.

Discussion

35.	Lines of magnetic flux which are parallel and in the same direction __________ each other.(a) Attract(b) Repel(c) Intersect(d) CancelThe question was asked during an online exam.This intriguing question comes from Characteristics of Lines of Magnetic Flux in section Electromagnetism of Basic Electrical Engineering
Answer» Correct choice is (B) Repel The best explanation: Lines of MAGNETIC FLUX which are parallel to each other and in the same direction repel each other because they TEND to act as like poles and like poles repel each other.

Discussion

36.	Magnetic field lines form _________ loops from pole to pole.(a) Open(b) Closed(c) Branched(d) Either closed or branchedThis question was addressed to me during an online exam.Query is from Characteristics of Lines of Magnetic Flux in chapter Electromagnetism of Basic Electrical Engineering
Answer» Right answer is (b) CLOSED For explanation I would say: Magnetic FIELD lines form closed LOOPS from pole to pole. There is no discontinuity in the magnetic flux lines.

Discussion

37.	According to _________________ induced emf is equal to rate of change of magnetic flux.(a) Newton’s law(b) Lenz law(c) Faraday’s law(d) Coulomb’s lawThis question was posed to me during an online interview.Origin of the question is Magnitude of the Generated or Induced EMF topic in division Electromagnetism of Basic Electrical Engineering
Answer» RIGHT answer is (c) Faraday’s law For EXPLANATION: ACCORDING to Faraday law of electromagnetic INDUCTION, induced EMF is equal to rate of change of magnetic flux.

Discussion

38.	What is the principle of the transformer?(a) Gauss law(b) Coulomb’s law(c) Electromagnetic induction(d) Ampere’s lawI have been asked this question in homework.Question is taken from Magnitude of the Generated or Induced EMF topic in chapter Electromagnetism of Basic Electrical Engineering
Answer» Right OPTION is (C) Electromagnetic induction To ELABORATE: In TRANSFORMER, flux in secondary coil change due to CURRENT in the primary coil and hence current get induced in secondary coil.

Discussion

39.	If net force is zero on a particle in magnetic field what is relation between velocity and magnetic field?(a) v=EB(b) v=E/B(c) v=B/E(d) v=1/(EB)I got this question in examination.This is a very interesting question from Force Determination in chapter Electromagnetism of Basic Electrical Engineering
Answer» Right choice is (b) v=E/B Explanation: SINCE NET force is ZERO on the particle. Electric force = Magnetic force QE = QvB => E=vB or v=E/B.

Discussion

40.	The unit for force in a current carrying conductor is _________(a) TeslaAmperemetre(b) Tesla(c) Ampere/metre(d) Ampere*metreI have been asked this question in a national level competition.The query is from Force Determination topic in portion Electromagnetism of Basic Electrical Engineering
Answer» The correct option is (a) TESLAAmperemetre The BEST explanation: F=Bil. So,UNIT of force=unit of B * unit of i * unit of l = TeslaAmperemetre.

Discussion

41.	The relation between the direction of current and the direction of the force is ________(a) Same direction(b) Opposite direction(c) Perpendicular(d) UnrelatedThe question was posed to me in a job interview.My question is from Force on a Current Carrying Conductor in division Electromagnetism of Basic Electrical Engineering
Answer» The correct choice is (C) Perpendicular The explanation is: When a CONDUCTOR carries a CERTAIN value of CURRENT, the force developed in the conductor, the current in the conductor and the MAGNETIC field in the conductor are mutually perpendicular to each other.

Discussion

42.	Magnetic field is strong when____________(a) magnetic field lines are closer(b) magnetic field lines are farther(c) magnetic field lines are longer(d) magnetic field lines are thickerThis question was addressed to me by my college professor while I was bunking the class.Query is from Characteristics of Lines of Magnetic Flux in division Electromagnetism of Basic Electrical Engineering
Answer» Correct option is (a) magnetic field lines are CLOSER To EXPLAIN: Magnetic field is STRONG where magnetic field lines are closer and weak where magnetic field lines are farther.

Discussion

43.	The relation between the direction of induced emf and the direction of motion of the conductor is?(a) Parallel(b) Equal(c) Not related(d) PerpendicularI got this question during an interview.This intriguing question comes from Direction of Induced EMF topic in portion Electromagnetism of Basic Electrical Engineering
Answer» Correct option is (d) Perpendicular Easy explanation: ACCORDING to Fleming’s right hand RULE, the induced EMF, the motion of the conductor and the MAGNETIC flux are mutually perpendicular.

Discussion

44.	According to Fleming’s right hand rule, the thumb points towards?(a) Current(b) E.M.F.(c) Motion of the conductor(d) Magnetic fluxI had been asked this question by my college director while I was bunking the class.I want to ask this question from Direction of Induced EMF in division Electromagnetism of Basic Electrical Engineering
Answer» Correct answer is (c) Motion of the conductor For explanation I WOULD say: FLEMING’s LEFT hand rule stated that if the index finger points toward magnetic flux, the thumb TOWARDS the motion of the conductor, then the middle finger points towards the induced emf.

Discussion

45.	Force in current carrying conductor placed in magnetic field is ___________ of il and B.(a) dot product(b) scalar product(c) cross product(d) vector additionI have been asked this question in an online quiz.My query is from Force Determination in section Electromagnetism of Basic Electrical Engineering
Answer» The CORRECT choice is (C) cross product Easy explanation: Force in a CURRENT CARRYING conductor is given by cross product of il and B.

Discussion

46.	What happens to the magnetic field in the solenoid when the number of turns increases?(a) Increases(b) Decreases(c) Remains constant(d) Becomes zeroI have been asked this question in an interview.Origin of the question is Magnetic Field of a Solenoid topic in division Electromagnetism of Basic Electrical Engineering
Answer» The correct choice is (a) Increases For explanation I would say: The magnetic field of a SOLENOID is directly proportional to the NUMBER of TURNS in it. Hence as the number of turns increases, the magnetic field ALSO increases.

Discussion

47.	If a coil is wound around a steel core and electric current is passed through the coil, the steel core acts as a?(a) Electromagnet(b) Permanent magnet(c) Neither electromagnet nor permanent magnet(d) Either electromagnet or permanent magnetThe question was asked at a job interview.Enquiry is from Magnetic Field of a Solenoid topic in chapter Electromagnetism of Basic Electrical Engineering
Answer» Right answer is (b) Permanent magnet The best explanation: When a coil is wound around a steel CORE, the steel core behaves like a permanent magnet because it is a ferromagnetic material and once it becomes MAGNETIC it does not LOSE its magnetic property.

Discussion

48.	Magnetic field at a point d distance away from long wire due to electric current i in it is ____________(a) µ0i/2r(b) µ0i/r(c) µ0i/2πr(d) µ0i/πrI had been asked this question by my college director while I was bunking the class.This intriguing question comes from Magnetic Field Due to an Electric Current topic in portion Electromagnetism of Basic Electrical Engineering
Answer» The correct choice is (C) µ0i/2πr The EXPLANATION: Magnetic FIELD at distance d from LONG wire with carrying current i is given by- B = µ0i/2πr.

Discussion

49.	The relation between the direction of current and the direction of magnetic field is ________(a) Same direction(b) Opposite direction(c) Perpendicular(d) UnrelatedThis question was posed to me in a job interview.My question comes from Direction of Magnetic Field topic in portion Electromagnetism of Basic Electrical Engineering
Answer» CORRECT OPTION is (c) PERPENDICULAR To elaborate: When a conductor carries a CERTAIN value of current, the force developed in the conductor, the current in the conductor and the magnetic FIELD in the conductor are mutually perpendicular to each other.

Discussion

50.	Magnetic field lines ___________ at the south pole.(a) Emerge(b) Converge(c) Neither emerge nor converge(d) Either emerge or convergeThe question was asked during an online exam.This interesting question is from Direction of Magnetic Field in chapter Electromagnetism of Basic Electrical Engineering
Answer» The correct ANSWER is (b) Converge For explanation: Magnetic FIELD lines converge at the south pole. Field lines SEEM to converge at the south pole because they END at the south pole.

Discussion

Explore topic-wise InterviewSolutions in .

What is the consequence of motor effect?(a) Current(b) Voltage(c) Electromagnetic induction(d) EMFI had been asked this question during an internship interview.The origin of the question is Electromagnetic Induction topic in division Electromagnetism of Basic Electrical Engineering

Field lines move from __________(a) North to south(b) South to north(c) West to east(d) East to westThis question was posed to me in exam.This intriguing question originated from Direction of Magnetic Field topic in section Electromagnetism of Basic Electrical Engineering

Can we see magnetic flux lines?(a) Yes(b) No(c) Depends on the strength of the field(d) Only when the field strength is very largeThe question was asked during an online interview.Query is from Magnetic Field topic in division Electromagnetism of Basic Electrical Engineering

What happens to the current in a coil while accelerating a magnet inside it?(a) Increases(b) Decreases(c) Remains constant(d) ReversesThis question was addressed to me in final exam.The question is from Electromagnetic Induction in portion Electromagnetism of Basic Electrical Engineering

Magnetic field lines seek the path of __________ resistance.(a) Maximum(b) Minimum(c) Infinite(d) ZeroI had been asked this question in final exam.My question is based upon Characteristics of Lines of Magnetic Flux topic in chapter Electromagnetism of Basic Electrical Engineering

What is the strength of magnetic field known as ________(a) Flux(b) Density(c) Magnetic strength(d) Magnetic flux densityI got this question in an interview for internship.I would like to ask this question from Magnetic Field topic in division Electromagnetism of Basic Electrical Engineering

Magnetic field lines ___________ at the north pole.(a) Emerge(b) Converge(c) Neither emerge nor converge(d) Either emerge or convergeThe question was posed to me in an interview.My question is from Direction of Magnetic Field in section Electromagnetism of Basic Electrical Engineering

What happens to the magnetic field in the solenoid when the length of the solenoid increases?(a) Increases(b) Decreases(c) Remains constant(d) Becomes zeroThe question was asked in exam.Question is taken from Magnetic Field of a Solenoid in section Electromagnetism of Basic Electrical Engineering

Magnetic field lines form _________ loops from pole to pole.(a) Open(b) Closed(c) Branched(d) Either closed or branchedThis question was addressed to me during an online exam.Query is from Characteristics of Lines of Magnetic Flux in chapter Electromagnetism of Basic Electrical Engineering

What is the principle of the transformer?(a) Gauss law(b) Coulomb’s law(c) Electromagnetic induction(d) Ampere’s lawI have been asked this question in homework.Question is taken from Magnitude of the Generated or Induced EMF topic in chapter Electromagnetism of Basic Electrical Engineering

The unit for force in a current carrying conductor is _________(a) Tesla*Ampere*metre(b) Tesla(c) Ampere/metre(d) Ampere*metreI have been asked this question in a national level competition.The query is from Force Determination topic in portion Electromagnetism of Basic Electrical Engineering

Magnetic field lines ___________ at the south pole.(a) Emerge(b) Converge(c) Neither emerge nor converge(d) Either emerge or convergeThe question was asked during an online exam.This interesting question is from Direction of Magnetic Field in chapter Electromagnetism of Basic Electrical Engineering

The unit for force in a current carrying conductor is _________(a) TeslaAmperemetre(b) Tesla(c) Ampere/metre(d) Ampere*metreI have been asked this question in a national level competition.The query is from Force Determination topic in portion Electromagnetism of Basic Electrical Engineering