PC Electrical Theory & Principles 3

Question 1

Three resistors of 6Ω, 12Ω, and 4Ω are connected in parallel. What is the total equivalent resistance?

Accepted Answer

2Ω

Answer

1/Rt = 1/6 + 1/12 + 1/4 = 2/12 + 1/12 + 3/12 = 6/12; Rt = 2Ω.

Question 2

In a parallel circuit, which quantity remains the same across all branches?

Accepted Answer

Voltage

Answer

Voltage is identical across all branches in a parallel circuit.

Question 3

Kirchhoff's Current Law (KCL) states that:

Accepted Answer

The sum of currents entering a node equals the sum leaving it

Answer

KCL states that the algebraic sum of all currents at any node equals zero — what enters must leave.

Question 4

A capacitor in a DC circuit, after fully charging, acts like a(n):

Accepted Answer

Open circuit

Answer

A fully charged capacitor blocks DC current, effectively acting as an open circuit.

Question 5

Capacitance is measured in which unit?

Accepted Answer

Farad (F)

Answer

Capacitance is measured in Farads (F), with practical values often in microfarads (µF) or picofarads (pF).

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