State any four precautions to be taken while using an Ammeter and Voltmeter.

State any four precautions to be taken while using an Ammeter and Voltmeter. 
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1 Answer

Answer :

Precautions to be taken while using Ammeters:

Ammeters are to be connected in series of circuits.

1. While connecting ammeters across emf source always a series resistance should be used.

This is necessary to limit the current passing through meter.

2. The polarity of the meter should be first observed & then it should be connected accordingly. The reverse polarity may damage the pointer of meter.

3. While using the multi range ammeter, first use highest current range & then go on decreasing range until good upscale reading obtained.

Precautions to be taken while using Voltmeters:

1. The resistance of Voltmeter is very high & so while connecting Voltmeter, care should be taken that the Voltmeter is connected across (parallel) the circuit or component.

2. Polarity should be observed & connections should be accordingly made.

3. While using Voltmeter highest range should be used first &then range should be decreased.

4. Loading effect can be minimized by using high sensitivity
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