Question

For increasing the range of voltmeter, connect a:

• A. high value resistance in series with voltmeter
• B. low value resistance in series with voltmeter
• C. high value resistance in parallel with voltmeter
• D. low value resistance in parallel with voltmeter

Hint:

To extend a voltmeter’s range, always add a \textbf{high resistance in series}. For ammeters, use a \textbf{low resistance in parallel}.

Answer 1

The Correct Option is A

A voltmeter is designed to measure the potential difference between two points.
It must be connected in parallel with the component across which the voltage is to be measured.
To increase the range of a voltmeter (i.e., to allow it to measure higher voltages), a high resistance is added in series with it.
This additional resistance drops part of the voltage, ensuring that only a fraction of the total voltage appears across the internal voltmeter coil.
This technique allows the voltmeter to measure larger voltages without damaging the sensitive internal mechanism.
Connecting resistance in parallel would defeat the purpose and alter the parallel voltage measurement logic.
Hence, a high-value series resistor is the correct method to increase the range.