The current 𝐼 in the circuit shown is ________.

 

Solution for Current I

Given:

• Voltage source = 5 V
• Three resistors = 2 kΩ each
• Current source = 1 mA (upward)

Step 1: Label the Nodes

Bottom wire is ground (0 V).
Left node: VA = 5 V
Middle node: VB
Right node: VC

Step 2: Apply KCL at Node C

(VC − VB) / 2000 = 1 × 10⁻³

Therefore,

VC = VB + 2

Step 3: Apply KCL at Node B

(VB − 5)/2000 + VB/2000 + (VB − VC)/2000 = 0

Substitute VC = VB + 2:

(VB − 5)/2000 + VB/2000 − 2/2000 = 0

Multiply by 2000:

VB − 5 + VB − 2 = 0

2VB = 7

VB = 3.5 V

Step 4: Calculate Current I

I = (5 − 3.5)/2000

I = 0.00075 A

I = 0.75 mA

Final Answer

I = 0.75 mA (flowing from left to right).

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