What Is EMF? Where (-) ive sign shows decrease in area. A metre scale is also attached on the wooden board. This shows that we can calculate the EMF if we know the voltage across the terminals, the current flowing and the internal resistance of the cell. (ii) changing the area A of the coil inside the magnetic field, EMF can be stated as the work done per unit of charge and the SI unit of Electromotive force is Volt. Q.1: Consider that we have a circuit with a potential difference of 3.2 V, with a current of 0.6 A. As the current is changing periodically that is why it is called as alternating current. To assist you with that, we are here with notes. The induced emf can be produced in a coil by , where E is the energy and Q is the charge. CGS unit of φ = maxwell, 1 weber = 108 maxwell. Procedure. If the area within the magnetic field changes, then emf will be induced. As sinωt is a periodic function,therefore it varies from -1 to +1. Simulator. Candidates who are ambitious to qualify the Class 12 with good score can check this article for Notes. NOTE: Lenz’s law is a consequence of the law of conservation of energy. this chemistry formula sheet for Electrochemistry is highly recommended for the quick revision of the entire chapter-Electrochemistry  . The rectangular loop enters the magnetic field and goes out of the field. Induced emf e=- N (dΦ/dt); where N = number of turns. Here (V) means the voltage of the cell, (I) means the current in the circuit and (r) means the internal resistance of the cell. First Law Whenever magnetic flux linked with the closed loop or circuit changes, an emf induces in the loop or circuit which lasts so long as change in flux continuous. Candidates who are ambitious to qualify the Class 12 with good score can check this article for Notes.

(ii) The induced emf lasts so long as the change in magnetic flux continues. Direction of the current in the circuit changes by the up and down movement of the loops.
Minimum value of e= - NBAω and maximum value of e=+ NBAω. It is a scalar quantity. Video .

K = √M / L1 L2, where L1 and L2 are coefficients of self-induction of the two coils and M is coefficient of mutual induction of the two coils. 7. Copyright © 2020 Entrancei. The generation of alternating currents (ac) is based on the phenomenon of electromagnetic induction. Download the free Pdf of chapter-Electrochemistry formula for class 12 chemistry . This mechanical energy is getting converted toinduce emf because of which induced current is produced. Whenever the magnetic flux changes an emf will be induced in the coil. The material of wire should have a high resistivity and low temperature coefficient. An electrical generator is a device that converts mechanical energy to electrical energy. (iv) When strength of current flowing in a coil is increased or decreased, induced current is developed in the coil in same or opposite direction. (i) putting the coil/loop/circuit in varying magnetic field.

ie;                                                     and, Developed by Amrita Vishwa Vidyapeetham & CDAC Mumbai. Magnetic Flux The magnetic flux linked with any surface is equal to total number of magnetic lines of force passing normally through it. Chemistry Notes With the help of Notes, candidates can plan their Strategy for particular weaker section of the subject and study hard. Coefficient of coupling is maximum (K = 1) in case (a), when coils are coaxial and minimum in case (b), when coils are placed a right angles. It means, if a loop is placed on the right side of a straight current carrying conductor and the current in the conductor is increasing, then induced current in the loop is anticlockwise, (ii) ®IN In ® IN suppose the magnetic field in the loop is perpendicular to paper inwards ® and this field is increasing, then induced current in the loop is anticlockwise, If a rod of length 1 moves perpendicular to a magnetic field B, with a velocity v, then induced emf produced in it given by, If a metallic rod of length 1 rotates about one of its ends in a plane perpendicular to the magnetic field, then the induced emf produced across its ends is given by. Mock test are the practice test or you can say the blue print of the main exam. 3. CBSE Class 12 Physics Chapter 6 Electromagnetic Induction notes in PDF are available for free download in myCBSEguide mobile app. Electromotive Force (emf) OR Cell Potential. Electromotive force (emf) is a measurement of the energy that causes current to flow through a circuit. Do find the detail NCERT solutions for class 11 chemistry prepared by expert faculty of entrancei.
N = total number of turns in the solenoid, 1 = length of the coil, n = number of turns in the coil and, If core of the solenoid is of any other magnetic material, then, Self – inductance of a toroid L = μo N2 A / 2πr, Energy stored in an inductor E = 1 / 2 LI2. Question from very important topics is covered by Exemplar Questions for Class 12. Theory. The direction of induced current in any conductor can be obtained from Fleming’s right hand rule. Candidates can click on the subject wise link to get the same. Candidates who are pursuing in Class 12 are advised to revise the notes from this post.