The induced e.m.f. is directly proportional to N, the total number of turns in the coil. The induced e.m.f. is directly proportional to A, the area of cross-section of the coil. The induced e.m.f. is directly proportional to B, the strength of the magnetic field in which the coil is rotating.
What are the factors that depend emf of the wire in a magnetic field?
induced e.m.f for a coil of wire depends on four things:
- Magnetic strength of the core in the coil of wire. (stronger –> bigger emf)
- Number of turns of wire in the coil (more turns –> bigger emf)
- The cross-sectional area of the coil (bigger area –> bigger emf).
- How fast you move the magnet into/out of the coil.
Does emf depend on speed?
Back EMF in practice
Back EMF is directly related to speed, so when the speed decreases, so does the induced back EMF.
Is emf depend on resistance?
From the formula, it is evident that the induced EMF does not depend on the resistance of the coil or wire. However, if the induced EMF produces a current, then that produced current will depend on the resistance of the coil or wire.
What are the three factors that determine the amount of emf produced?
The size of the voltage can be varied by three factors:
- The size of the magnetic field. The more flux lines there are, the more flux lines there are for the conductor to cut.
- The active length of the conductor.
- The speed at which the conductor passes through the field.
How do you increase emf?
Increasing the strength of the magnetic field – If the same coil of wire is moved at the same speed through a stronger magnetic field, there will be more emf produced because there are more lines of force to cut.
What four factors affect the magnitude of the induced emf in a coil of wire?
The area of the coil, how long it takes for changes to occur, how many turns of wire in coil, or the magnetic field part that’s perpendicular to the plane of the coil could affect the magnitude of induced emf in a wire coil.
What are the factors on which emf induced in alternator depends write the expression for emf?
EMF Equation of Alternator
- = Number of poles.
- φ = Flux per pole in webers.
- = Rotor speed in RPM.
- = Frequency of the induced EMF in Hz.
- = Number of conductors in series per phase.
- = Number of coils or turns per phas
What are the factors that affect the magnitude of the induced emf and the induced current’s magnitude and direction?
- The number of turns of the coil:As the number of turns increases, the magnitude of the induced current increases.
- The speed of the relative motion of the conductor and the magnetic field: As the speed of the relative motion of the magnet increases, the magnitude of the induced current increases.
What does the direction of the induced emf depends on?
The time in which the magnetic flux changes. DIRECTION of induced e.m.f depends on whether the magnetic flux increases or decreases.
Is emf independent of resistance?
The emf of the cell is the electrical potential (voltage) developed within the cell due to electro-chemical reactions. It is ideally independent of the external resistance of a circuit and the current drawn.
Which are the factors on which the direction of induced current in electromagnetic induction depend?
1 Answer
- Direction of magnetic field.
- Direction of conductor.
- Direction of induced current.
Does induced emf depends on current?
No. The EMF induced into the conductor depends only on the change of the magnetic field relative to the circuit.
What are the factors affecting the induced emf of the transformer?
The factors on which the magnitude of the induced emf in the secondary coil of the transformer depends on:
- The relative positioning of the two coils:
- Positioning them on a common soft iron core:
- Increasing the number of turns:
What are the three factors that determine the induced voltage of a coil of conductors?
The factors that determine how much voltage is induced due to electromagnetic induction in a circuit are;
- The number of turns in the coil around the core.
- The rate at which the magnetic field changes.
- The strength or size of the magnetic field.
- The speed at which the conductor passes through the field.
What increases electromagnetic field?
A simple electromagnet consisting of a coil of wire wrapped around an iron core. A core of ferromagnetic material like iron serves to increase the magnetic field created. The strength of magnetic field generated is proportional to the amount of current through the winding.
How do you strengthen a solenoid’s magnetic field?
The strength of the magnetic field around a solenoid can be increased by:
- increasing the number of turns on the coil.
- increasing the current.
- placing an iron core inside the solenoid.
How is emf induced in alternator?
When the rotor rotates, the stator conductors which are static in case of alternator cut by magnetic flux , they have induced EMF produced in them (according to Faraday’s law of electromagnetic induction which states that if a conductor or coil links with any changing flux, there must be an induced EMF in it.
Which emf is induced in alternator?
The emf induced by the alternator or synchronous generator is three-phase alternating in nature.
Is induced emf independent of time?
In electro magnetic induction, the induced emf is independent of weber i.e., pole strength. It depends on change in flux, time and the magnetic field strength.
Why is emf induced?
Definition. It can be defined as the generation of a potential difference in a coil due to the changes in the magnetic flux through it. In simpler words, electromotive Force or EMF is said to be induced when the flux linking with a conductor or coil changes.
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