Magnetic Circuit and Electromagnetism - Rise of Current in an inductive circuit
1 Answer
An inductive circuit consists of an inductor, which is a passive electronic component that stores energy in the form of a magnetic field when current flows through it. When there is a change in current in an inductive circuit, Faraday's law of electromagnetic induction comes into play. This law states that a change in magnetic flux through a loop of wire induces an electromotive force (EMF) or voltage in that loop.
When the current in an inductive circuit is increased, the magnetic field around the inductor expands. This expansion of the magnetic field results in a change in magnetic flux through the circuit. According to Faraday's law, this change in magnetic flux induces a voltage in the circuit, opposing the change in current that caused it. This phenomenon is known as self-induced electromotive force or self-inductance.
Mathematically, the relationship between the induced voltage (
ind
V
ind
) and the rate of change of current (
/
di/dt) in an inductor is given by:
ind
=
−
V
ind
=−L
dt
di
Where:
ind
V
ind
is the induced voltage (in volts)
L is the inductance of the inductor (in henrys)
dt
di
is the rate of change of current (in amperes per second)
From this equation, you can see that the induced voltage is directly proportional to the rate of change of current and the inductance of the circuit. The negative sign indicates that the induced voltage opposes the change in current.
When the current in an inductive circuit is increasing (di/dt is positive), the induced voltage will be negative, leading to a "back EMF" that resists the increase in current. This effect is commonly observed in scenarios where you suddenly apply a voltage across an inductor or when the current is rapidly increasing, such as during the initial rise of current in an inductive circuit.
The energy associated with the magnetic field in the inductor is stored as potential energy, and when the current changes, this energy is either released (when the current decreases) or absorbed (when the current increases). This behavior is why inductors are often used to smooth out current variations and act as energy storage elements in circuits.
In summary, when the current in an inductive circuit increases, the magnetic field around the inductor expands, inducing a voltage that opposes the change in current. This phenomenon is described by Faraday's law of electromagnetic induction and is a fundamental concept in electromagnetism and circuit theory.
When the current in an inductive circuit is increased, the magnetic field around the inductor expands. This expansion of the magnetic field results in a change in magnetic flux through the circuit. According to Faraday's law, this change in magnetic flux induces a voltage in the circuit, opposing the change in current that caused it. This phenomenon is known as self-induced electromotive force or self-inductance.
Mathematically, the relationship between the induced voltage (
ind
V
ind
) and the rate of change of current (
/
di/dt) in an inductor is given by:
ind
=
−
V
ind
=−L
dt
di
Where:
ind
V
ind
is the induced voltage (in volts)
L is the inductance of the inductor (in henrys)
dt
di
is the rate of change of current (in amperes per second)
From this equation, you can see that the induced voltage is directly proportional to the rate of change of current and the inductance of the circuit. The negative sign indicates that the induced voltage opposes the change in current.
When the current in an inductive circuit is increasing (di/dt is positive), the induced voltage will be negative, leading to a "back EMF" that resists the increase in current. This effect is commonly observed in scenarios where you suddenly apply a voltage across an inductor or when the current is rapidly increasing, such as during the initial rise of current in an inductive circuit.
The energy associated with the magnetic field in the inductor is stored as potential energy, and when the current changes, this energy is either released (when the current decreases) or absorbed (when the current increases). This behavior is why inductors are often used to smooth out current variations and act as energy storage elements in circuits.
In summary, when the current in an inductive circuit increases, the magnetic field around the inductor expands, inducing a voltage that opposes the change in current. This phenomenon is described by Faraday's law of electromagnetic induction and is a fundamental concept in electromagnetism and circuit theory.