Objective Electromagnetic Induction Questions and Answers pdf

31. A conductor carries 125 amperes of current under 60° to a magnetic field of 1.1 tesla. The force on the conductor will be nearly
(a) 50 N
(b) 120 N
(c) 240 N
(d) 480 N
Ans: b

32. Find the force acting on a conductor 3m long carrying a current of 50 amperes at right angles to a magnetic field having a flux density of 0.67 tesla.
(a) 100 N
(b) 400 N
(c) 600 N
(d) 1000 N
Ans: a

33. The co-efficient of coupling between two air core coils depends on
(a) self-inductance of two coils only
(b) mutual inductance between two coils only
(c) mutual inductance and self inductance of two coils
(d) none of the above
Ans: c

34. An average voltage of 10 V is induced in a 250 turns solenoid as a result of a change in flux which occurs in 0.5 second. The total flux change is
(a) 20 Wb
(b) 2 Wb
(c) 0.2 Wb
(d) 0.02 Wb
Ans: d

35. A 500 turns solenoid develops an average induced voltage of 60 V. Over what time interval must a flux change of 0.06 Wb occur to produce such a voltage ?
(a) 0.01 s
(b) 0.1 s
(c) 0.5 s
(d) 5 s
Ans: c

36. Which of the fpllowing inductor will have the least eddy current losses ?
(a) Air core
(b) Laminated iron core
(c) Iron core
(d) Powdered iron core
Ans: a

37. A coil induces 350 mV when the current changes at the rate of 1 A/s. The value of inductance is
(a) 3500 mH
(b) 350 mH
(c) 250 mH
(d) 150 mH
Ans: b

38. Two 300 uH coils in series without mutual coupling have a total inductance of
(a) 300 uH
(b) 600 uH
(c) 150 uH
(d) 75 uH
Ans: b

39. Current changing from 8 A to 12 A in one second induced 20 volts in a coil. The value of inductance is
(a) 5 mH
(b) 10 mH
(c) 5 H
(d) 10 H
Ans: c

40. Which circuit element(s) will oppose the change in circuit current ?
(a) Resistance only
(b) Inductance only
(c) Capacitance only
(d) Inductance and capacitance
Ans: b

Read More Questions:
Electromagnetic Induction Part1
Electromagnetic Induction Part2
Electromagnetic Induction Part3
Electromagnetic Induction Part4
Electromagnetic Induction Part5