What Is Induced EMF in Electro-Magnetic Induction?

[dirk diggler]

What does 'Induced EMF' mean?

Describe clearly the principles of 'Self Induction'

What is the unit of Inductance?

A Coil has self-inductance if 0.25H. Calculate the induced EMF if the current changes from 100mA to 350mA in 25mS

Calculate the inductance of a circuit in which an EMF of 30V is induced, when the circuit's rate of change is 200A/sec.


Thanks - need help or answers asap.

 

[HallsofIvy]

If you really really need those answers fast why not just look in a textbook? You are, after all, just asking for basic definitions.

 

[M98Ranger]

Electro-Magnetic Induction refers to the phenomenon where an electric current is induced in a conductor when it is placed in a changing magnetic field. This is based on the principle discovered by Michael Faraday in the 19th century, which states that a changing magnetic field can create an electric current in a conductor.

Induced EMF, or Electromotive Force, refers to the voltage that is induced in a conductor when it is moved through a magnetic field or when the magnetic field around it changes. It is the force that drives the flow of electric current in a conductor.

Self Induction is a process where the changing magnetic field produced by a current in a conductor induces an opposing voltage in the same conductor. This is due to the fact that a changing current creates a changing magnetic field, and this changing magnetic field then induces a voltage in the same conductor. This phenomenon is described by Faraday's Law of Induction.

The unit of Inductance is the Henry (H), named after Joseph Henry, another scientist who contributed to the discovery of electromagnetism. It is defined as the amount of inductance in a circuit where an induced EMF of one volt is produced when the current in the circuit changes at a rate of one ampere per second.

To calculate the induced EMF in a circuit with a self-inductance of 0.25H, we can use the formula EMF = L x (di/dt), where L is the inductance and (di/dt) is the rate of change of current. Plugging in the values, we get EMF = 0.25H x (0.35A-0.1A)/0.025s = 6V.

For the inductance of a circuit, we can rearrange the formula to get L = EMF/(di/dt). Substituting the given values, we get L = 30V/200A/s = 0.15H.

I hope this helps answer your questions. Let me know if you need any further clarification.