JOIN ADRE 2.0 Telegram Group

Electromagnetic Induction MCQs for NEET

Questions
1 The magnetic flux (∅) lined with a coil is related to its area (s) as:
A ∅ ∝ s
B ∅ ∝ s²
C ∅ ∝ s1/2
D ∅ ∝ s-1/2

Answer:∅ ∝ s
2 If the magnetic flux linked with a coil through which a current off ampere is set up is ∅, then the coefficient of self-inductance of the coil is:
A l/∅
B ∅/l
C ∅l
D None of these

Answer:∅/l
Advertisement
Article and Schedule Quiz Start Test!

DOWNLOAD CURRENT AFFAIRS PDF FROM APP

3 The magnetic flux (∅) linked with a coil is related to the number of turns (N) ofthe coil as:
A f ∝ N
B f ∝ N-1
C f ∝ N2
D f ∝ N-2

Answer:f ∝ N
4 A transformer is used to light 100 W and 110 V lamp from a 220 V mains. If the main current is 0.5 A. Then the efficiency of the transformer is:
A 11%
B 50%
C 80%
D 90%

Answer:90%
5 An e– and a p– are moving parallel to each other in a magnetic field. The magnetic force acting on the p+ is:
A 1840 times that on e–
B less than that of e–
C same as that of e–
D slightly more than that of e–

Answer:same as that of e–
6 The magnetic field is parallel to a surface, then the magnetic flux through the surface is :
A zero
B small but not zero
C infinite
D large but not infinite

Answer:small but not zero
7 In a uniform magnetic field B, a wire in the form of a semicircle of radius r rotated about the diameter of the circle with angular frequency ‘ω’. The axis of rotation is perpendicular to the field. If the total resistance of the circuit is R the mean power generated per period of rotation is :
A Class 12 Physics Chapter 6 Electromagnetic
B Class 12 Physics Chapter 6 Electromagnetic
C Class 12 Physics Chapter 6 Electromagnetic
D Class 12 Physics Chapter 6 Electromagnetic

Answer:B
8 In the expression e = –d∅/dt, the -ve sign signifies:
A The induced emf is produced only when magnetic flux decreases
B The induced emf opposes the change in the magnetic flux
C The induced emf is opposite to the direction of the flux
D None of these

Answer:The induced emf opposes the change in the magnetic flux
9 The coupling co-efficient of the perfectly coupled coils is:
A Zero
B 1
C slightly more than 1
D infinite

Answer:1
10 The core of a transformer is laminated because:
A rusting of core may be prevented
B ratio of voltage in primary and secondary may be increased.
C energy losses due to eddy current may be minimised
D The weight of transformer may be reduced

Answer:energy losses due to eddy current may be minimised
11 The flux linked with a coif at any instant t is given by ∅ = 10t² – 50t + 250. The induced emf at t = 35 is:
A 10 V
B 190 V
C -190 V
D -10 V

Answer:-10 V
12 When the magnetic field is parallel to a surface, then the magnetic flux through the surface is:
A infinite
B zero
C small but not zero
D large but not infinite.

Answer:zero
13 Two coils of self inductance 2 mil and 8 mil are placed so close together that the effective flux in one coil is completely linked with other. The mutual inductance between these coils is :
A 4 mH
B 16 mH
C 10 mH
D 6 mH

Answer:10 mH
14 For purely capacitive circuits, power factor is:
A 0
B -1
C 1
D infinity

Answer:0
15 A choke is used as a resistance in :
A dc circuits
B ac circuits
C both ac and dc circuits
D neither (a) nor (b)

Answer:ac circuits
16 If I current is flowing inductance L, then the dimension of 3/2 LI² is equivalent to:
A charge
B force
C momentum
D energy

Answer:momentum
17 A metal conductor of length 1 m rotates vertically about one of its ends at angular velocity 5 rad s-1 . If the horizontal component of earth’s magnetism is 2 × 10-5 T, then e.m.f. developed between the two ends of the conductor is:
A 5 µV
B 50 µV
C 5 mV
D 50 mV

Answer:5 µV
18 1 henry is equal to :
A Class 12 Physics Chapter 6 Electromagnetic
B Class 12 Physics Chapter 6 Electromagnetic
C weber ampere
D None of these

Answer:A
19 The phase difference between the flux linkage and the emf in a rotating coil in a uniform magnetic field is:
A zero
B π/2
C π/4
D π

Answer:π/4
20 Which of the following is not equal to a henry?
A Class 12 Physics Chapter 6 Electromagnetic
B Class 12 Physics Chapter 6 Electromagnetic
C Class 12 Physics Chapter 6 Electromagnetic
D Class 12 Physics Chapter 6 Electromagnetic

Answer:C

ADRE 2.0 FULL LENGTH MOCK TEST

Take Mock Tests

Missiles Mock Test Start Test!
SSC MTS Mock Test Start Test
IBPS CLERK MOCK TEST Start Test
SSC MTS 2022 JULY 26 Shift 1 (ENGLISH) Start Test!
SSC GD Previous Year Paper 2021 Nov 17 Shift - I (Hindi) Start Test!
SSC CGL Tier - 1 PYP 2022 April 21 Shift- 1 (ENGLISH) Start Test!
MPSC PAPER I MOCK TEST 1 (ENGLISH) Start Test!
IB Security Assistant Mock test 1 (english) Start Test!
UP POLICE CONSTABLE MOCK TEST 1 Start Test!
DELHI POLICE CONSTABLE MOCK TEST 1 (HINDI) Start Test!

Chapters

Advertisement
Assam Direct Recruitment Test Series