Electromagnetic-Induction-Quiz-1

Electromagnetic Induction Quiz-1

Dear Readers,

As per analysis for previous years, it has been observed that students preparing for NEET find Physics out of all the sections to be complex to handle and the majority of them are not able to comprehend the reason behind it. This problem arises especially because these aspirants appearing for the examination are more inclined to have a keen interest in Biology due to their medical background. 

Furthermore, sections such as Physics are dominantly based on theories, laws, numerical in comparison to a section of Biology which is more of fact-based, life sciences, and includes substantial explanations. By using the table given below, you easily and directly access to the topics and respective links of MCQs. Moreover, to make learning smooth and efficient, all the questions come with their supportive solutions to make utilization of time even more productive. Students will be covered for all their studies as the topics are available from basics to even the most advanced. 

Q1. A wire of length 1 m is moving at a speed of 2ms^-1 perpendicular to its length and in a homogenous magnetic field of 0.5 T. The ends of the wire are joined to a circuit of resistance 6 Ω. The rate at which work is being done to keep the wire moving at constant speed is

•  1/12 W
•  1/6 W
•  1/3 W
•  1 W

Solution
                        

Q2.A horizontal loop abcd is moved across the pole pieces of a magnet as shown in fig. with a constant speed v. When the edge ab of the loop enters the pole pieces at time t=0 sec, which one of the following graphs represents correctly the induced emf in the coil  

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Solution
When loop enters in field between the pole pieces, flux linked with the coil first increases (constantly) so a constant emf induces. When coil enters completely within the field, there is no flux change, so e=0 When coil exists, flux linked with the coil decreases, hence again emf induces, but in opposite direction

Q3.  An ideal transformer has 100 turns in the primary and 250 turns in the secondary. The peak value of the ac is 28 V. The r.m.s. secondary voltage is nearest to

•  50 V
•   70 V
•  100 V
•  40 V

Solution
                       

Q4. Which of the following is not an application of eddy currents

•  Induction furnace
•  Galvanometer damping
•  Speedometer of automobiles
•  X-ray crystallography

Solution
X-ray crystallography

Q5.Induced emf in the coil depends upon

•  Conductivity of coil
•  Amount of flux
•  Rate of change of linked flux
•  Resistance of coil

Solution
                        

Q6. A square metallic wire loop of side 0.1 m and resistance of 1Ω is moved with a constant velocity in a magnetic field of 2 wb/m² as shown in figure. The magnetic field is perpendicular to the plane of the loop, loop is connected to a network of resistances. What should be the velocity of loop so as to have steady current of 1mA in loop

                             

•  1 cm/sec
•  2 cm/sec
• 3 cm/sec
•  4 cm/sec

Solution
                       

 

Q7.When a certain circuit consisting of a constant e.m.f. E, an inductance L and a resistance R is closed, the current in it increases with time according to curve 1. After one parameter (E,L or R) is changed, the increase in current follows curve 2 when the circuit is closed second time. Which parameter was changed and in what direction

                                   

•  L is increased
•  L is decreased
•  R is increased
•  R is decreased

Solution
                      

Q8.The average power dissipation in pure inductance is

•  1/2 LI²
•  2LI²
•  1/4 LI²
•  Zero

Solution
Zero

Q9.The current from A to B is increasing in magnitude. What is the direction of induced current, if any, in the loop shown in figure.

                                        

•  No current is induced
•  Clock-wise current
•  Anti-clock-wise current
•  Alternating current

Solution
Magnetic flux through the loop is upward and its is increasing due to increasing current along AB. Current induced in the loop should have magnetic flux in the downward direction so at to oppose the increase in flux. Therefore, current induced in the loop is clockwise.

Q10. The current i in an induction coil varies with time t according to the graph shown in figure. Which of the following graphs shows the induced emf (e) in the coil with time

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Solution