Question

The current flowing through a resistor connected in a circuit and the potential difference developed across its ends are as shown in the diagram by milliammeter and voltmeter readings respectively:

What are the least counts of these meters ?
What is the resistance of the resistor ?

Answer 1

Answer:

Explanation:

Least Count

Least count of ammeter = 10 mA

Least count of Voltmeter = 0.1 V

Resistance

R = V/I

Voltmeter Reading = 2.4 V

Milliammeter Reading = 250 mA = 0.25 A

So, R = 2.4/0.25 = 9.6 ohm

Answer 2

Answer:

LC of ammeter =  0.2 / 10

= > 0.02 A

A = 0.02 A

LC of Voltmeter =  1 / 10

= > 0.1 V

V = 0.1 V

Current = 15 x 0.02 A = 0.3 A

Potential difference = 21 x 0.1 V = 2.1 V