Answer :
The minimum potential difference measured
by a voltmeter between the two given
terminals is called the least count of that voltmeter.
Two given marks of the \(voltmeters = 0 and 0.5 V\)
\(Potential difference = 0.5 – 0 = 0.5V\)
\(No. of divisions between these two marks = 20\)
\(\implies frac{0.5}{20}\)
\(\implies least count = 0.024\)