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A DC generator works on the principle of
Lenz's law
Ohm's law
Faraday's law of electromagnetic induction
None of the above
Faraday's law of electromagnetic induction
A DC generator is an electromechanical device that converts mechanical energy into electrical energy. It operates on Faraday's Law of Electromagnetic Induction, which states that an electromotive force (EMF) is induced in a conductor whenever it cuts across a magnetic field.
A DC generator is an electromechanical device that converts mechanical energy into electrical energy. It operates on Faraday's Law of Electromagnetic Induction, which states that an electromotive force (EMF) is induced in a conductor whenever it cuts across a magnetic field.
e=тИТNdtd╧ХтАЛ тАФ Induced EMF based on rate of change of flux
E=60A╧ХZNPтАЛ тАФ EMF equation for a DC generator
When a coil (armature) is rotated in a stationary magnetic field provided by the field poles, the magnetic flux linkage of the coil changes with time. According to Faraday's law, this change in flux induces an EMF in the coil. For a DC generator, this alternating induced EMF is converted into unidirectional (DC) output using a mechanical commutator and brushes.
Mechanical energy is converted into electrical energy using electromagnetic induction.
The commutator acts as a mechanical rectifier to ensure unidirectional current.
Fleming's Right-Hand Rule determines the direction of the induced current.
The magnitude of the induced EMF depends on the flux density, speed of rotation, and number of conductors.
Provides stable DC voltage output
Suitable for high-power industrial applications
Requires constant maintenance of brushes and commutator
Prone to sparking at the commutator surface
DC arc welding
Battery charging systems
DC motor drive systems
Lenz's Law (Option A) determines the direction of the induced EMF but is not the principle of energy conversion itself.
Ohm's Law (Option B) relates voltage, current, and resistance in a circuit, not the mechanism of generating electricity.
C is correct тАФ A DC generator generates electrical energy by electromagnetic induction as defined by Faraday's Law.
Always remember: Generators use Faraday's law of induction (mechanical to electrical), while Motors use the Lorentz force law (electrical to mechanical).