Question

In the circuit shows in Fig. `6.22`, a voltmeter reads `30 V` when it is connected across a `400 omega` resistance. Calculate what the same voltmeter would read when it is connected across the `300 Omega` resistance.

Answer 1

The voltmeter will show maximum reading if it draw minimum current and maximum current flows through `AB` it is an if the maximum of voltmeter is high .Which is in case i.e.
The voltmeter will is show minimum reading if a draws more current it is so if the resistance of voltmeter is low which in is case c becomes the effective resistance of less then the least resistance connected in parallel