The main reason for using ac is safety.
ac as more safe than the dc as it passes through zero in every half cycle.
There are many other reasons like,
ac can be transmitted for longer distances efficiently
we can use the Induction motor.
assuming you mean electromotive force: emf is the main principle behind power transformers. emf also comes in the form of radio waves, which are used for radio transmission (obviously)
Believe it is called EMF, Electrical Motive Force.
The EMF of a battery made up of cells in series is equal to the sum of the EMFs of the individual cells. When cells are connected in series, their voltages add up. For example, if you have two 1.5V cells in series, the total EMF of the battery would be 3V.
You can measure the emf of a cell by using a voltmeter, as this draws current from a cell. You can use the voltage, the emf, and the load resistance to determine the internal resistance of the cell.
By using a power supply of greater 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.
emf in volts
Bcoz the emf which is to be measured is less than emf of driving cell....
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.
EMF is greater
EMF - band - was created in 1989.
EMF - band - ended in 2009.