Difference between ammeter and voltmeter | Ammeter vs Voltmeter

Ammeter and voltmeter are electrical instruments and need electricity as well as a complete electric circuit to display reading. The main key difference between the ammeter and voltmeter are discussed in this tutorial on the basis of certain important factor such as connection with some uses, safety, resistance, ideal behaviour, measuring units, applications, etc. 

Before we learn about the key difference between ammeter and voltmeter first let us understand the definition of ammeter and voltmeter. 

Definition of ammeter: 

The ammeter is many more advantages of measuring the instrument which is used to measure the current in all the circuits.  It measures the small amount of current in must in mA or in microampere. The ammeter is placed in series with the measuring circuit so that the whole current of the circuit passes through it.

Definition  of voltmeter:

The voltmeter is the voltage measuring device. It is basically connected in parallel with the electrical circuit whose potential is to be measured. The connection polarity of the voltmeter is the same as that of the ammeter.

The main key difference between ammeter and voltmeter are given below.
  • The ammeter is defined as the device used for measuring the small value current flow in the circuit, while in voltmeter measure the potential difference between any two points of the electrical circuit. 
  • The ammeter representation of an ammeter circuit with A while in voltmeter the circuit denoted by a circle with V inside it.  
  • The ammeter measures the current in amperes or even smaller units mA or microampere while in voltmeter measures the difference in volts. 
  • The accuracy of the ammeter is much more as compared to the voltmeter.
  • The measuring range of the voltmeter can be increases or decreases by changing the value of resistance whereas the rage of ammeter can not be changed.
  • The resistance of the ammeter is low while the internal resistance of the voltmeter is very low so that the current from the circuit does not disturb the measuring of the voltmeter. 
  • The ammeter is connected in series with the circuit for measuring the complete current whereas the voltmeter is connected in parallel with the circuit.  
  • In ammeter, a large amount of current passes through while in voltmeter is a very small amount of current passes.
  • In ammeter low resistance to electricity so must not e connected straight across the supply while in voltmeter high resistance to electricity so e able to be connected across the supply.
  • The resistance of an ideal ammeter is zero but in resistance of an ideal voltmeter is infinity.
  • The circuit must be disconnected from the power source in order to attach the ammeter while in voltmeter circuit does not need to be disconnected to attached the voltmeter.
  • An ammeter can be created by attaching a small resistance in parallel with the galvanometer whereases in voltmeter can be created by attaching a very high resistance in series with the galvanometer.
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