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In the op-amp circuit given below the load current i_L is

1. – V_s
  R₂
2. V_s
  R₂
3. V_s
  R_L
4. V_s R_L

Correct Option: A

V_A = V_B (due to virtual ground)
KCL at node B

	V_β	+	V_B – V_o	+ i_L = 0 .............(i)
	R₂		R₂

KCL at node A

	V_A – V_s	+	V_A – V_o	= 0 .............(ii)
	R₁		R₁

V_A = V_s ·	R₁	+ V_o ·	R₁
	R₁ + R₁		R₁ + R₁

V_A =	V_s	+	V_o	= V_B
	2		2

	V_s + V_o		V_s + V_o	– V_o
=	2	+	2		= – i_o

	R₂		R₂

V_s	= – i_o
R₂

– i_o =	V_s
	R₂