Hint – In an ideal voltmeter we want to have negligible or zero potential drop and the resistance is connected in series, use this concept.
Complete step-by-step answer:
As we know that the internal resistance is connected in series with the voltmeter.
So in ideal voltmeter the value of internal resistance is zero so that there will be zero voltage drop in the internal resistance.
As if the value of internal resistance is not zero then there will be a voltage drop which is equal to the product of current and resistance and the voltmeter could not deliver to its maximum instance.
Practically there is some internal resistance but ideally the internal resistance is zero.
So the value of internal resistance in ideal voltmeter is zero.
Note – Internal resistance refers to the opposition to the flow of current offered by cells and batteries themselves, in this case it refers to the resistance offered by the voltmeter. A voltmeter is an instrument used for measuring electrical potential difference between two points in an electric circuit.