Question 1

What does Kirchhoff's junction rule state?

Accepted Answer

The algebraic sum of currents at a junction is zero. This expresses conservation of charge: current is not used up when branches meet. In the displayed direction, if I1 enters while I2 and I3 leave, then I1 = I2 + I3.

Question 2

What does Kirchhoff's loop rule mean?

Accepted Answer

The algebraic sum of all potential changes around any closed loop is zero. Traversing a discharging cell from negative to positive gives +E, while the external and internal resistance terms carry the appropriate signed current for the direction of traversal.

Question 3

How do n identical cells combine in series?

Accepted Answer

For n identical cells, each with emf E and internal resistance r, series connection gives E_eq = nE and r_eq = nr. The same current flows through every cell. A loaded cell has terminal voltage V = E - Ir.

Question 4

How do n identical cells combine in parallel?

Accepted Answer

When n identical cells are connected in parallel with the same polarity, E_eq = E and r_eq = r/n. Every cell has the same terminal voltage, and identical cells share the total current equally. The supplied load current remains load-dependent.

Question 5

How are an ammeter and a voltmeter connected?

Accepted Answer

An ammeter is connected in series in the branch whose current is being measured. A voltmeter is connected in parallel across the two points between which the potential difference is required.

Kirchhoff's Laws & Cells in Series/Parallel — The Two-Loop Circuit Board

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