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EMF is electromotive force. It is another name for voltage. Voltage is electric potential in joules per coulomb.
Current is electric flow, in amperes. Amperes are coulombs per second.
Voltage and current are not the same thing, and "emf current", or "voltage current" does not make sense.
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∙ 12y ago
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Why emf of battery driving potentiometer is greater than emf of the cell to be measured?
Bcoz the emf which is to be measured is less than emf of driving cell....
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.....
While discharging which is greater TPD or EMF?
EMF is greater
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.
Can terminal potential difference be greater than the emf supplied?
All cells have internal resistance. When connected to a load, the resulting load current results in an internal voltage drop across the internal resistance. This voltage drop acts in the opposite sense to the cell's e.m.f., thus causing its terminal voltage to fall below that of the e.m.f. The greater the load current, the greater the difference between the terminal voltage and the e.m.f.
When is the terminal potential difference of a battery greater than its emf?
When it is being loaded.
Three similarities between pd and emf?
Both emf and pd have the same unit. namely volt Both have the same definition. It is the work performed in moving unit positive charge right from one point to the other against the electric field. Both are got by the product of current and resistance. But emf is the pd across of a cell or source when it is not in action. So emf is slightly greater than the pd in the circuit as there may be a little bit of internal resistance.
Difference between back EMF and induced EMF?
An induced electromotive force (emf) is an induced voltage. Voltage (emf) causes current flow, and this induced voltage will cause a current that is called the induced current.We might also add that the induced current will cause a magnetic field to expand about the current path, and this field will "sweep" the conductor. The sweeping of the conductor by that expanding magnetic field will set up an emf that will oppose the emf that was creating it.CommentTechnically, there is no such thing as an 'induced current'. It is voltage that is induced. Any current flows as a result of that induced voltage being applied to a load. But that current is certainly NOT induced!
When in drive it goes reverse?
if the generated emf in motor is greater than supply voltage means the drive will goes to reverse
What does the size of the current depend on?
A: The EMF and total resistance
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
What happens to the generated voltage of a self excited generator if shunt field resistance is greater than the critical resistance?
it doesn't develop emf ..........
