1. Md.Kausher ahmed Electrical department

2. Advanced electricity Code-6722

3. Lesson declared Mutual inductance

4. Learning outcomes After finished this lesson student will able to # What is mutual inductance. #Draw the equation of mutual inductance.

5. Mutual Inductance When an emf is produced in a coil because of the change in current in a coupled coil, the effect is called mutual inductance. The emf is described by Faraday's law and it's direction is always opposed the change in the magnetic

6. Continue……… field produced in it by the coupled coil Lenz's law ). The induced emf in coil 1 is due to self inductance L. The induced emf in coil #2 caused by the change in current I 1 can be expressed as

7. Continue……..

8. Fig :Mutual Inductance

9. Continue…… The mutual inductance M can be defined as the proportionalitiy between the emf generated in coil 2 to the change in current in coil 1 which produced it.

10. This is some other topics about subject Discharge lamp A discharge lamp has a glass or silica envelope containing two metal electrodes separated by a gas. Gases used include, neon, argon, xenon, sodium, metal halide, and mercury. The core operating principle is much the same as the carbon arc lamp, but the term 'arc lamp' is normally used to refer to carbon arc lamps,

11. Continue……. with more modern types of gas discharge lamp normally called discharge lamps. With some discharge lamps, very high voltage is used to strike the arc. This requires an electrical circuit called an igniter, which is part of the ballast circuitry. After the arc is struck, the internal

12. Continue……. resistance of the lamp drops to a low level, and the ballast limits the current to the operating current. Without a ballast, excess current would flow, causing rapid destruction of the lamp. Some lamp types contain a little neon, which permits striking at normal running voltage, with no external ignition circuitry. Low pressure sodium lamps operate this way.

13. The simplest ballasts are just an inductor, and are chosen where cost is the deciding factor, such as street lighting. More advanced electronic ballasts may be designed to maintain constant light output over the life of the lamp, may drive the lamp with a square wave to maintain completely flicker-free output, and shut down in the event of certain faults.

14. Note In every day every lecture we will learn more And more. And every lecture we will learn some topic to know about basic thing. So keep reading.

15. Feedback What is mutual inductance? Draw the equation of mutual inductance.

16. Thanks to all