Difference between Voltmeter and Potentiometer
The Potentiometer (Pot meter) and voltmeter both are the electronic devices which measures voltage in the circuit. Voltmeter is an electronic instrument that measures voltages of either direct or alternating electric current in volts, from the scale of millivolts to kilovolts .In todays era there are digital voltmeter which gives higher order accuracy, but as a practicle purpose we use analog voltmeter only. A potentiometer is a passive electronic component. Potentiometers work by varying the position of a sliding contact across a uniform resistance. Generally the potentiometer is more sensitive than the voltmeter. The potentiometer accurately measures the potential difference it has zero internal resistance. The voltmeter has high internal resistance which affect in the measurement.
Voltmeter |
Potentiometer |
1)The voltmeter is electronic equipment which measures the voltage in the electric circuit.
2) Measurement of EMF of cell by voltmeter is done approximately. 3) The resistance of voltmeter high but finite when me measure the EMF of the cell. 4) Voltmeter is not useful for measure the internal resistance of the cell. 5) We can get direct reading by voltmeter. 6) Voltmeter is less accurate and sensitive. 7) Potential difference measured by voltmeter is less than the actual potential difference. 8) Voltmeter is based on the deflection method. 9) The voltmeter has tendency to draws some current from emf source. 10) The voltmeter is two terminal device. |
1) The potentiometer is itself a variable resistor which is used to adjust the resistance in the circuit.
2) Measurement of EMF of cell by potentiometer is done accurately. 3) The resistance of Potentiometer become infinite when me measure the EMF of cell. 4) Potentiometer is useful for measuring the internal resistance of the cell. 5) We cannot get direct reading by potentiometer. 6) potentiometer is more accurate and sensitive. 7) Potential difference measured by potentiometer is equal to actual potential difference. 8) Potentiometer is based on zero deflection method. 9) Potentiometer does not have tendency to draw any electric current from the source of emf. 10) The potentiometer is three terminal device. |