A current of 3 A flows through the 2 Ω resistor shown in the circuit. The power dissiated in the 5 Ω resistor is

diagram

4 W

2 W

1 W

5 W

Answer

5 W

Voltage across 2 Ω is same as voltage across arm containing 1 Ω and 5 Ω resistance.
Voltage across 2 Ω resistance,
V = 2 x 3 = 6 V
So, voltage across lowest arm,
V₁ = 6 V
Current across 5 Ω, I = 6/ 1+6 = 1 A
Thus, power across 5 Ω,
P = I²R = (1)² x 5 = 5 W