Question

in lab we measured voltage with a multimeter and got good results for circuits that contained resistors 1 to 10k ohms in series and poor results for resistances 1 - 10M ohms in series explain how considering the multimeter as real meter vs an ideal meter helps to explain the discrepancy

Answer 1

part 1

If you take the multi meter with higher resistance than the voltage drop across it more and it is not allowed to show the actual value of voltage which is to be measured, and hence it would give poor result.

But in other case there is multi meter with low resistance having small voltage drop across the meter and therefore meter would be able to read correct value. hence it will give good result.

part 2

In ideal meter value of internal resistance of the meter should be zero so that voltage drop across the multemetr will zero. If it would happpen than the all voltage of the circuit can be measured.

But practically it is not posible. there is always some internal resistance of the meter and due to this some voltage drop across it. Hence generally meter have some error.