The voltage marked Vx is given by

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The voltage marked V_x is given by—

1. 60 V
  7
2. 120 V
  7
3. 40 V
  7
4. None of these.

Correct Option: B

Apply superposition theorem to solve this problem
Case I. Take 8A current source the circuit becomes

current in 2 Ω resistance, i.e.

I ₁ = 8 ×		5	=	40	amp. → (i) (A → B)
		5 + 2		7

Case II. Take 20 V voltage source: the circuit becomes
Note: Here the resistance connected in the arm CD is the extra redundant element because voltage their resistance in independent.

I = I₂ =		20	=	20	amp
		5 + 2		7

which is also flowing in 2 Ω resistance. (A → B) so, the net current in the 2 resistance

=		40	+	20	=	60	(∵ I = I₁+ I₂)
		7		7		7

Voltage (V_x) = 2 ×		60	=	120	V
		7		7