Concepts Of Physics MCQ Edition [Volume 2]PhysicsElectric Current in Conductors

Determine the current in the 20 resistor for the circuit shown in the figure.

Options

A0.1 A
B0.2 A
C0.4 A
D0.5 A

Correct answer

B. 0.2 A

Step-by-step solution

Taking the potential at node B as 0 V and at node A as V_A . Applying Kirchhoff's Current Law (KCL) at node A: V_A - 5 10 + V_A - 0 20 + V_A - 5 10 = 0 Multiplying the equation by 20 to clear the denominators: 2(V_A - 5) + V_A + 2(V_A - 5) = 0 2V_A - 10 + V_A + 2V_A - 10 = 0 5V_A = 20 V_A = 4 V The current through the 20 resistor is: I = V_A - V_B 20 = 4 - 0 20 = 0.2 A

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