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# What are the source of DC EMF?

## What are the source of DC EMF?

Direct current is produced by sources such as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. A direct current circuit is an electrical circuit that consists of constant voltage sources, constant current sources, and resistors.

### What is EMF in DC circuits?

Electromotive force (EMF) is equal to the terminal potential difference when no current flows. EMF and terminal potential difference (V) are both measured in volts, however they are not the same thing. EMF (ϵ) is the amount of energy (E) provided by the battery to each coulomb of charge (Q) passing through.

#### What are the 5 sources of EMF?

The five sources of EMF are: Electromagnetism, Photoelectric, Thermoelectric, Piezoelectric and Chemical. Thermoelectric: A transfer of heat energy directly to electric energy.

What is DC circuits?

Direct Current (DC) is the constant flow of Electric Charge from high to low Potential. A Direct Current circuit is a circuit that Electric Current flows through in one direction. DC is commonly found in many low-voltage applications, especially where these are powered by Battery.

What are three sources of EMF?

Main Sources of Electromotive Force A few of the examples of electromotive force include electrochemical cells, thermoelectric devices, solar cells, electrical generators, transformers, etc.

## What are two sources of EMF?

Devices that can provide emf include electrochemical cells, thermoelectric devices, solar cells, photodiodes, electrical generators, transformers and even Van de Graaff generators. In nature, emf is generated when magnetic field fluctuations occur through a surface.

### Is back emf AC or DC?

Back EMF can have either a sinusoidal (AC) or a trapezoidal (DC) waveform. The shape of the back EMF is important, as it determines the type of drive current and commutation method that should be used for the motor.

#### What is back emf of A dc motor?

Back emf is the generator output of a motor, and so it is proportional to the motor’s angular velocity ω. It is zero when the motor is first turned on, meaning that the coil receives the full driving voltage and the motor draws maximum current when it is on but not turning.

What are three sources of emf?

What are three types of DC circuits?

The DC electric circuit is mainly classified into three groups. They are the series DC circuit, parallel DC circuit, and series and parallel DC circuit.