Why can a null measurement be more accurate than one using standard voltmeters and ammeters? What factors limit the accuracy of null measurements?

zi2lalZ 2020-12-25 Answered
Why can a null measurement be more accurate than one using standard voltmeters and ammeters?
What factors limit the accuracy of null measurements?
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Expert Answer

Liyana Mansell
Answered 2020-12-26 Author has 97 answers
Step 1
A null measurement be more accurate than one using standard voltmeters and ammeters because standard measurements of voltage and current alter circuits. There are numerical uncertainties in standard measurement of voltage and current. Current flow reduced by an ammeters and voltmeter draws more current.
In null measurement circuit does not alter. In null measurement voltage balance and no current passing through the measuring device.
Step 2
factors which are affects the null measurement:
-Resistance of wiring

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