Question

A resistor of unknown resistance is connected in series to a 3-ohm resistor. The voltmeter in the 3-ohm resistor registers 4 V and in the unknown one 6 V. What is the resistance of the unknown resistor?

Answer 1

Explanation:

Given,

R1 =? R2 = 3ohm

V1 = 6V. V2 = 4V

As I is constant in series,

So,I = 4/3 = 1.33A

So, R1 = 6/1.33 = 4.51ohm

Therefore,R1 = 4.51ohm