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Normally emf can be calculated by the following formula
e=N*(dф/dt) where dф/dt = rate of change of flux linkages
In actual practice it is given as e=-[N*(dф/dt) ] because as per lenzs law the voltage induced in a direction to oppose the very cause for it i.e., change in flux linkages.
vydehi
Wiki User
∙ 13y ago
Wiki User
∙ 10y agoBack EMF refers to electromotive force that opposes the current flow in a particular circuit. Calculation of the average back EMF requires specific details about the circuit.
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How do you prove the existence of back EMF?
How do you proof of the existence of back emf ?
Does motional emf call induced emf?
yes indused emf is also called motional emf. If an open coil is subjected to a variable magnetic field, at the ends of the coil a potential difference is induced which is called induced emf. If a coil is connected to an emf source and switched on, the rising current will produced an variable magnetic field which in turn produces an emf. It is called back emf.
What does an increase in field strength in a dc generator causes a?
increased Back emf
How are emf measured?
emf in volts
While discharging which is greater TPD or EMF?
EMF is greater
How do you prove the existence of back EMF?
How do you proof of the existence of back emf ?
Can back emf in an inductor be in the same sense as emf of source?
yes..only the application is different.
Does motional emf call induced emf?
yes indused emf is also called motional emf. If an open coil is subjected to a variable magnetic field, at the ends of the coil a potential difference is induced which is called induced emf. If a coil is connected to an emf source and switched on, the rising current will produced an variable magnetic field which in turn produces an emf. It is called back emf.
What is Counter Force?
It is also called back EMF. Back EMF is the electric potential difference that opposes the current that induces it. See related link below.
What is Back emf of DC motor?
In dc motor, the armature conductors are revolving in the magnetic field and emf is induced in the armature conductors. The direction of the induced emf is in opposite direction to the applied voltage as per Flemings left hand rule. So, the induced emf in motor is called as back emf or counter emf. Vydehi
What is counter electro-magnteic force?
It is also called back EMF. Back EMF is the electric potential difference that opposes the current that induces it. See related link below.
What is emf induced in a motor's coil that tends to reduce the current in the coil of the motor?
BACK emf induced in a motor's coil that tends to reduce the current in the coil of the motor. The answer should be 'back'.
What is the Opposition to current flow in a inductive ac circuit?
Back EMF.
What is significance of back emf?
According to motor eq. Eb=v-Ia.Ra.And the speed of motor is directly proportional to back EMF.At starting of motor speed is 0,so that Eb is also 0.As the speed increases ,Eb also increases,so that armature current decreases.As the Eb decreases ,so that Ia increases.In this way the back EMF makes the motor self regulating to take armature current as per requriment of motor.Because of this reason EMF also called governor principle of DC motor.This is most important significance of Back EMF. The back EMF is Explaned with lenses Law
What is the significance of emf?
According to motor eq. Eb=v-Ia.Ra.And the speed of motor is directly proportional to back EMF.At starting of motor speed is 0,so that Eb is also 0.As the speed increases ,Eb also increases,so that armature current decreases.As the Eb decreases ,so that Ia increases.In this way the back EMF makes the motor self regulating to take armature current as per requriment of motor.Because of this reason EMF also called governor principle of DC motor.This is most important significance of Back EMF. The back EMF is Explaned with lenses Law
The back emf indcuced in the armature is AC or DC?
only in dc motor...
What does an increase in field strength in a dc generator causes a?
increased Back emf
