Question
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
Solution
D.
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
