Question

In the circuit shown above, what is the resistance R?

(A) 3 Ω 

(B) 4 Ω 

(C) 6 Ω 

(D) 12 Ω 

(E) 18 Ω

Answer 1

The correct option is: (B) 4 Ω 

Explanation:

The current through R is found using the junction rule at the top junction, where 1 A + 2 A enter giving I = 3 A. Now utilize Kirchhoff’s loop rule through the left or right loops: (left side) + 16 V – (1 A)(4 Ω) – (3 A)R = 0 giving R = 4 Ω