Electromagnetic Induction Practice Questions
Class 12 · Physics · 2198 free MCQs with instant results and detailed explanations.
2198
Total
770
Easy
1040
Medium
388
Hard
Start Practicing Electromagnetic Induction
Take a timed quiz or customize your practice session
Topics in Electromagnetic Induction
Lenz's Law
600
Eddy Currents
669
Faraday's Law
476
Self and Mutual Inductance
453
Sample Questions from Electromagnetic Induction
Here are 10 sample questions. Start a quiz to get randomized questions with scoring.
Q1
Easy
What does Faraday's Law of Electromagnetic Induction state about induced electromotive force (emf)?
A.
It is directly proportional to the rate of change of magnetic flux.
B.
It is directly proportional to the product of current and resistance.
C.
It is inversely proportional to the area of the conductor.
D.
It is independent of the magnetic field strength.
Show Answer & Explanation
Correct Answer: A
Faraday's Law states that the induced electromotive force in any closed circuit is proportional to the rate of change of magnetic flux through the circuit.
Q2
Easy
When a magnet is moved towards a coil, what is the effect on the induced current in the coil according to Lenz's Law?
A.
The induced current flows in a direction to oppose the motion of the magnet.
B.
The induced current increases the motion of the magnet.
C.
The induced current has no effect on the magnet's motion.
D.
The induced current will always be in the same direction as the magnet's motion.
Show Answer & Explanation
Correct Answer: A
Lenz's Law states that the direction of induced current is such that it opposes the change that produced it, hence it opposes the approach of the magnet.
Q3
Easy
What is Faraday's first law of electromagnetic induction?
A.
The induced electromotive force (emf) in a circuit is proportional to the rate of change of magnetic flux.
B.
Magnetic fields can be created by both stationary and moving charges.
C.
The total magnetic flux through a closed surface is always zero.
D.
An induced current always opposes the change that produces it.
Show Answer & Explanation
Correct Answer: A
Faraday's first law states that the induced emf is directly related to the rate of change of magnetic flux.
Q4
Medium
If a magnet is moved towards a conducting loop, what happens to the current induced in the loop?
A.
It increases steadily
B.
It decreases steadily
C.
It flows in one direction only
D.
It depends on the speed of the magnet
Show Answer & Explanation
Correct Answer: D
The current induced in the loop depends on the speed of the magnet's movement. Faster movement induces a larger current due to more rapid change in magnetic flux.
Q5
Medium
A coil with 50 turns has an area of 0.2 mยฒ. If the magnetic field changes from 0.1 T to 0.3 T in 3 seconds, what is the average induced emf?
A.
1.0 V
B.
2.0 V
C.
0.5 V
D.
1.5 V
Show Answer & Explanation
Correct Answer: A
Average induced emf = -N * (ฮB/ฮt) * A. Here, ฮB = 0.3 - 0.1 = 0.2 T, and ฮt = 3 s. Thus, emf = -50 * (0.2/3) * 0.2 = -1.0 V.
Q6
Medium
What happens to the induced emf in a circuit if the magnetic field is reversed?
A.
It remains the same
B.
It decreases
C.
It becomes negative
D.
It becomes zero
Show Answer & Explanation
Correct Answer: C
Reversing the magnetic field changes the direction of the induced emf, making it negative (if we consider the value to be negative) according to Lenz's Law.
Q7
Medium
If the resistance of a coil is 10 ohms and the induced emf is 2 V, what is the induced current in the coil?
A.
0.1 A
B.
0.2 A
C.
0.3 A
D.
0.4 A
Show Answer & Explanation
Correct Answer: B
Using Ohm's law: I = V/R, where V = 2 V and R = 10 ohms; thus, I = 2/10 = 0.2 A.
Q8
Hard
A loop of wire is placed in a uniform magnetic field. If the angle between the normal to the loop and the magnetic field is 30 degrees, how does the induced emf change when the angle is decreased to 0 degrees?
A.
Increases
B.
Decreases
C.
Remains constant
D.
Becomes zero
Show Answer & Explanation
Correct Answer: A
The induced emf is directly related to the rate of change of magnetic flux. As the angle decreases, the effective area exposed to the magnetic field increases, hence inducing a greater emf.
Q9
Hard
A solenoid with a length of 2 m and a cross-sectional area of 0.01 mยฒ carries a current of 5 A. If the current is changed to 10 A in 0.1 seconds, what is the induced emf in a loop placed inside the solenoid?
A.
0.15 V
B.
0.2 V
C.
0.1 V
D.
0.25 V
Show Answer & Explanation
Correct Answer: B
The induced emf in the loop can be calculated using Faraday's law. The change in magnetic field inside the solenoid leads to an induced emf proportional to the rate of change of current.
Q10
Hard
In an electromagnetic induction experiment, a magnet is dropped through a conducting loop. What happens to the induced current when the magnet is falling faster?
A.
Increases
B.
Decreases
C.
Remains the same
D.
Becomes zero
Show Answer & Explanation
Correct Answer: A
The induced emf is proportional to the rate of change of magnetic flux. A faster fall of the magnet increases this rate, leading to a stronger induced current.
Showing 10 of 2198 questions. Start a quiz to practice all questions with scoring and timer.
Practice All 2198 Questions →More Physics Chapters
1
Electric Charges and Fields
1994 Qs →
2
Electrostatic Potential and Capacitance
1749 Qs →
3
Current Electricity
1806 Qs →
4
Moving Charges and Magnetism
1980 Qs →
5
Magnetism and Matter
2260 Qs →
6
Alternating Current
2411 Qs →
7
Electromagnetic Waves
2877 Qs →
8
Ray Optics and Optical Instruments
2594 Qs →
Other Class 12 Subjects
Electromagnetic Induction โ Class 12 Physics Practice Questions Online
This page contains 2198 practice MCQs for the chapter Electromagnetic Induction in Class 12 Physics. The questions are organized by difficulty โ 770 easy, 1040 medium, 388 hard โ so you can choose the right level for your preparation.
Every question includes a detailed explanation to help you understand the concept, not just memorize answers. Take a timed quiz to simulate exam conditions, or practice at your own pace with no time limit. This chapter covers 4 topics, giving you comprehensive coverage of the entire chapter.