Question

Ideal Meters Problem. What internal resistance is ideal for a voltmeter? What internal resistance is ideal for an ammeter?

A. Infinity for both
B. Zero for both
C. Zero for ammeter; infinity for voltmeter
D. Infinity for ammeter; zero for voltmeter
E. None of these

Answer 1

C. Zero for ammeter; infinity for voltmeter

Step-by-step explanation:

Ammeter: A device that is used to measure the current through a circuit.

Voltmeter: A device that is used to measure the electric potential difference between two points in a circuit.

The relation among voltage (v), current (i), and resistance (r) is given as,

`v = i* r`

In ideal cases an ammeter must have zero resistance so that there is no voltage drop across it and accurate value of current will be measured.

In case of an ideal voltmeter, the resistance should be infinite so that the current across it is zero.