Question

What do you mean by electromagnetic induction? On what factors does the value of induced current in a circuit depend? Name and state the rule used for determination of direction of induced current. State the practical application of this phenomenon in everyday life. OR Draw a labelled circuit diagram of an electric generator and explain its principle and working.

Hint:

Fleming’s Right-Hand Rule helps determine the direction of induced current in generators, while the Left-Hand Rule is used for motors.

Answer 1

Electromagnetic Induction:
Electromagnetic induction is the phenomenon of generating an electric current in a conductor when it is placed in a changing magnetic field.
Factors affecting the induced current:

Magnitude of the change in magnetic field
Speed of motion of the conductor or the magnet
Number of turns in the coil
Area of the coil

Rule used to find direction of induced current:
Name: Fleming’s Right-Hand Rule
Statement: If the thumb, forefinger and middle finger of the right hand are stretched mutually perpendicular to each other, and the forefinger points in the direction of the magnetic field and the thumb in the direction of motion of the conductor, then the middle finger gives the direction of the induced current.
Practical Application:

The most common application is in electric generators, where mechanical energy is converted into electrical energy using electromagnetic induction.

OR Electric generator solution
Electric Generator: Principle and Working
Principle: It works on the principle of electromagnetic induction — when a coil rotates in a magnetic field, an induced current is produced in it.
Working:

A rectangular coil is rotated rapidly between the poles of a magnet.
The rotation changes the magnetic flux through the coil with time.
This induces current in the coil according to Faraday’s Law of Electromagnetic Induction.
The direction of current is given by Fleming’s Right-Hand Rule and changes every half rotation (in case of AC generator).
Diagram note \textit{Note: Add a labelled diagram of an electric generator with key components — coil, magnet, slip rings/commutator, brushes, etc.}