How will increasing the resistance of series resistor in voltmeter circuit change the max voltage measured???

Question

Will the maximum voltage increase, decrease, or remain the same?

Answer 1

if the series resistor is connected in series with the battery and the voltmeter

then the voltmeter will not read the full battery voltage because the voltage is shared across the series resistor and the voltmeter (any voltmeter has some resistance.

if the series resistor is Rs  and the voltmeter resistance is Rv then

volts read by voltmeter =  Vbattery x Rv/(Rv + Rs)

Answer 2

Not clear what you mean by "maximum voltage" which usually means the highest voltage you can apply to a meter without damage. Usually 1000 volts or higher.

You could increase this voltage by a large series resistor. If the voltmeter has a 10Mohm input resistance, adding an additional 10Mohm in series will double the max voltage. It will also change the readings, dividing by two.

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