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Only the relative direction they are moving. EMF, measured in Volts, travels along a conductor, perhaps because a magnetic field has built up around the conductor.
When that magnetic field collapses, CEMF, or counter-EMF is generated in the conductor, and it travels in the opposite direction of the original EMF, countering the original flow of electricity.
EMF is Electromotive Force, and is one component of measuring electricity. EMF is measured in Volts, and represents the 'pressure' moving the electricity along.
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What are the differences between potential difference and emf?
emf is present mainly in battery and potential difference is mainly present in circuit. emf is greater than p.d and p.d is greater than emf.......the units of both are Volt.....
A difference between electric forces and gravitational forces is that electrical forces include?
Electro-magnetism, or the electromotive force - EMF.
Can the potential difference across a battery be greater than its EMF?
If the emf of a battery is E Volt, the potential difference across a battery is given byV = E -I r where I is the current in the circuit and r is the inetrnal resistance.Hence E and V will be equal only when I = 0.The maximum potential difference across the battery will be equal to E only if I = 0.In gnereral potential difference can be equal or less than the emf.E.m.f can never exceed the potential difference.=====================================A battery charger is a device used to put energy into a secondary cell or (rechargeable) batteryby forcing an electric current through it.Hence to charge a battery another source of emf is needed.The combined emf is now will be (E - E1) where E is the emf of the battey in quesiton and E 1 is the emf of the external source used to charge the battery.Note that E-E1 will be negative in sign.======================================...A battery is charged only when its emf is less than its maximum emf.Suppose that the maximum emf of a cell is 1.5V. The battery should be charged only when its emf is less than 1.5 V say 0.5 V.To charge the cell we use a different source of emf E1 say 3V.The positive of the second source is connected to the negative of the cell so that theCombined emf is now 0.5 - 3 = -2.5V.The negative sign indicates that the emf is opposite to the emf of the cell which is 0.5V.Since the cell is getting charged, the difference in emf is gradually reduced to zero when the cell is fully charged.In modern charging units there are provisions so that the cell is never allowed to be over charged, even if the charging unit is in on for about 12 hours.When the cell is fully charged, (that is when the emf of the cell is now 1.5V), the potential difference between either the second source or cell will be zero.Taking into consideration the sign of the emf and the direction of current through the cell and the sign of the potential difference, the potential difference will be always less than the emf of the cell (which gradually increases while charging).Note that the potential difference is negative if the emf of the cell is taken as positive.Also note that the cell is charged only when its emf is less than its maximum e.m.f
Is potential difference always less than emf of the cell?
No. Because during charging process of a battery current flows in opposite direction to the discharging/consumption. so equation Emf=P.d. +Ir is changed to Emf=p.d. +Ir. Hence during charging process of a battery Potential difference is greater than electromotive force.
Is emf a scalar or vector quantity?
Emf has direction within a current loop, though it is not scalar. It's a bit between though as direction should be otherwise accounted for when discussing induced Emf. Not quite either.
What are the differences between potential difference and emf?
emf is present mainly in battery and potential difference is mainly present in circuit. emf is greater than p.d and p.d is greater than emf.......the units of both are Volt.....
What is the difference between the emf of a battery and the lost volts when discharging called?
Internal resistance
What is the difference between Counter-electromotive force and back emf?
They are Same for dc motor
What is the difference between emf and mmf?
emf is electromotive force mmf is magnetic motive force emf drives electon where as mmf drives magnetic field
Difference between voltage and emf?
'Voltage' is simply another term for 'potential difference', and an electromotive force is the open-circuit, or no-load, potential difference of a source such as a battery or generator.
What is the potential difference between two points in a circuit is called?
Voltage drop
A difference between electric forces and gravitational forces is that electrical forces include?
Electro-magnetism, or the electromotive force - EMF.
What is the difference between a DC motor and a generator in terms of EMF?
During the operation of a DC motor, EMF is created across its terminals using an external source. Whereas, in a DC generator EMF is created across its terminal based on principle of dynamically induced EMF. So talking in terms of EMF, in DC motor EMF is consumed by the motor coil and utilized to rotate the axle. On the other hand, in DC generator EMF developed across coil is transfered to a load or a battery and consumed by them.
Another name for EMF?
"Potential difference" or "Voltage".
Why volt meter is always placed in parallel?
Because the quantity it measures is 'EMF' or 'potential difference', that is,the difference in potential between two points. There may be 1 or 1,000circuit components between the two points.
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 cemf no abbreviation in creditcard?
what is the abbreviation for credit card charge
