Q. A voltmeter or an ammeter is more accurate.

Answer

In comparison to a voltmeter, an ammeter's readings are far more accurate than voltmeter. Changes to the resistance value expand or contract the voltmeter's measurement range, but do not affect the ammeters. Some current is measured directly, while most are measured indirectly by measuring the voltage across a precise resistor and then calculating the current using Ohm's law. Therefore, it is linked in parallel with the locations whose voltage is to be measured in order to obtain an accurate reading of the potential difference.