JEE Main 2022 | Electromagnetic Induction | Vidyut Chumbakiye Preran | RL Circuit

Quick Revision - Electromagnetic induction, AC Circuits

JEE Mains 2020 - 30 Days Revision | Electromagnetic Induction Part 1 - Important Questions | Physics

JEE Mains 2020 - 30 Days Revision | Electromagnetic Induction Part 2 - Important Questions | Physics

Explain the meaning of the word 'electromagnetic' and 'induction' in the term electromagnetic induction. On what factors does the value of the induced current produced in a circuit depend? Name and state the rule used for determination of direction of induced current. State one practical application of this phenomenon in everyday life.

Electromagnetic brakes work on the principle of electromagnetic induction. If a metallic disc or a coil is rotating in a uniform magnetic field, it will experience a torque due to induced currents set up in the disc. According to Lenz's law, induced current is in a direction so as to oppose the rotation. Hence a retarding torque is produced. The rotating wheel of a vehicle is connected to a coil placed in a uniform emf is used to charge a battery. Thus kinetic enery of wheel is stored as chemical energy. The drawback of electromagnetic brake is that induced current or retarding torque is directly proportional to speed of rotation. The speed, therefore, decays exponentially and vehicle will take a long time to stop. Thus, mechanical brakes are used simultaneously. The main disadvantage of electromagnetic brakes is that

Self inductance| Inductors and RL circuits

The phenomenon of generating current/e.m.f. in a circuit by changing magnetic field linked with the circuit is called electromagnetic induction (EMI). In our daily lives, we use (EMI) in many ways without even realiaing it. Read the above passage and answer the following question : (i) What is the most universal application of EMI ? (ii) How is the phenomenon being used to enhance the safety of all our important establishments ?

Questions based on Self inductance| Inductors and RL circuits

Assertion(A): Faraday's laws of electromagnetic induction are consequences of law of conservation of energy. Reason (R): The parameter LR in a L-R circuit has the dimension of time.

The Figure shows an electromagnetic gun. A bar of mass m, resistance R and length L is free to slide on two smooth rails separated by a distance L. A uniform magnetic field B is present perpendicular to the plane of the figure. A capacitor of capacitance C is charged using a battery of emf V_(0) by placing switch (S) at 1. To fire the gun (i.e., to impart a kinetic energy to the rod) the switch is shifted to position 2 after the capacitor is fully charged. The rails end abruptly at the point where the speed of the rod becomes maximum. The efficiency of the gun can be defined as the kinetic energy imparted to the bar divided by the energy spent by the battery while charging the capacitor. Calculate the efficiency of the gun. Neglect self inductance of the circuit.