The potentiometer and also the voltmeter both space the voltage measuring device. The significant difference in between the 2 is that the potentiometer steps the emf of the circuit whereas voltmeter measures the end terminal voltage that the circuit. The various other differences in between the potentiometer and also the voltmeter are explained listed below in the comparison chart.

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The potentiometer works on the rule of the compare method. The compares the unknown voltage resources by the conventional voltage source. Once their voltages space equal, the galvanometer reflects the null deflection. The voltmeter is connected in parallel through the circuit whose voltage is to it is in measured.

Content: Potentiometer Vs Voltmeter

Comparison Chart

Basis for Comparison Potentiometer Voltmeter
Definition It is one instrument offered for measure the unknown voltage.Type the meter designs for measuring the voltage.
Symbol
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Measure worth Accurately Approximately
Sensitivity High Low
Instrument kind Null Deflection TypeDeflection Type
ResistanceInfinite Very high yet measurable

Definition the Potentiometer

The potentiometer is the 3 terminal device used for measuring the unknown voltage source by comparing it with the known voltage. The standard source supplies the known voltage.

The potentiometer has seven thin wires ar parallels to every other. The one finish of the cable is attached to each various other with the assist of the copper strips. The copper strips convert the seven parallel wires into one. The battery and the change resistor is fastened in parallel with the emf source. 

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The one end of the unknown and known source is connected in parallel through each other. The other finish of the sources is linked to the two means switch. The galvanometer is connected to the other end of the switch. The jockey i beg your pardon is associated to the galvanometer is relocated on the wire till the galvanometer mirrors the null deflection.


Definition that Voltmeter

The voltmeter procedures the voltages between any kind of two clues of an electrical circuit. The voltmeter has actually high internal resistance due to the fact that of i m sorry the meter draws tiny current.

The working of the voltmeter relies on the high internal resistance. The voltmeter is of two types, i.e., the analogue or digital voltmeter. It is always connected in parallel with the circuit. 

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The current through the measurand resource passes through the high resistance circuit of the meter. In analogue voltmeter, the value of the unknown voltage is known by the product the the resistance, and the current flows with the circuit.


Key Differences between Potentiometer and Voltmeter

The following are the crucial differences in between potentiometer and voltmeter.

The potentiometer is one instrument provided for measuring the emf, vice versa, the voltmeter is a form of meter which measures the terminal voltage the the circuit.The potentiometer accurately actions the potential difference since of zero inner resistance. Whereas, the voltmeter has actually a high inner resistance which causes the error in measurement. Therefore the voltmeter approximately measures the voltage.The sensitivity of the potentiometer is very high, i.e. It deserve to measure small potential differences between the 2 points. The voltmeter has actually low sensitivity.The potentiometer uses the null deflection type instrument conversely, the voltmeter offers the deflection form instrument.The potentiometer has infinite internal resistance, whereas the potentiometer has actually high measurable resistance.

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Conclusion

The potentiometer and voltmeter both procedures the emf in volts. The potentiometer is offered in a circuit where the specific value of voltage is required. Because that approximate calculation, the voltmeter is used.