OAR OAR Mechanical Comprehension: Electricity 5

Question 1

A wire carries 2A of current. How many coulombs of charge pass through in 30 seconds?

Accepted Answer

60C

Answer

Charge Q = I × t = 2A × 30s = 60C.

Question 2

What does increasing the cross-sectional area of a conductor do to its resistance?

Accepted Answer

Decreases resistance

Answer

A larger cross-section provides more parallel paths for electrons, lowering resistance like widening a pipe reduces flow resistance.

Question 3

A diode allows current to flow in which direction?

Accepted Answer

Only from anode to cathode

Answer

A diode conducts current from anode to cathode (conventional current direction) and blocks reverse flow.

Question 4

What is the power factor in a purely resistive AC circuit?

Accepted Answer

1

Answer

In a purely resistive circuit, voltage and current are in phase, giving a power factor of 1 (unity).

Question 5

Which law states that the total current entering a junction equals the total current leaving it?

Accepted Answer

Kirchhoff's Current Law

Answer

Kirchhoff's Current Law (KCL) states that charge conservation requires all current entering a node to equal all current leaving it.

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