No links please
16. What is eddy current? Write an application of it. Define self inductance and mutual inductance. State the unit of self inductance.
[1 + 1 + 2 + 1]
Post multiple queries is different threads so that we can help you more efficiently as due to the paucity of time we can not solve all parts.
The answer to first two parts is below,
Eddy currents are the currents induced in a conductor when placed in a changing magnetic field.Whenever a conductor plate is moved through a magnetic field. There is a change of flux through the conductor area. The free electrons inside the conductor flow in circular loops to create eddy(whirl) of current.
Applications of Eddy Currents
Electromagnetic damping- Some galvanometers have a fixed core, which is made of non-magnetic metallic materials. When the coil oscillates, the eddy currents generated in the core oppose the motion and bring the coil to rest quickly.
Induction furnace- In an induction furnace, a very high temperature can be produced by producing large eddy currents.
Magnetic braking in trains- Strong electromagnets are situated above the rails in some electrically powered trains. When the electromagnets are activated, the eddy currents induced in the rails oppose the motion of the train.